451 4.4.0 DNS query failed

I was working on this annoying issue few days back, the mails sent to few domains are getting stuck in the queues on the Hub Transport server. The error message on the queue states 451 4.4.0 DNS query failed.

Well, it looked liked from here that there might be some issue with the DNS, ran few nslookup tests from the HUB servers itself, and surprisingly the domain and its MX records were resolving fine and i was able to connect to them absolutely fine.
More interestingly, if you hardcode the entry of the MX Record for that domain in the hosts file, the mails went through straight away.

I researched around few forum posts stated below, it seem like that this is a Bug with Exchange Server 2007 on Windows Server 2008, some issue related to IPv6.

Reference Posts:

http://social.technet.microsoft.com/Forums/en-US/exchangesvrtransport/thread/2e9a6263-7863-4d13-9480-7611db222e9e
http://social.technet.microsoft.com/Forums/en-US/exchangesvrtransport/thread/5ac614ee-e4fb-41d9-88f0-363f912634b1

Update Rollup 8 for Microsoft Exchange Server SP1 Released

Microsoft has released Update Rollup 8 for Microsoft Exchange Server 2007 Service Pack 1 (SP1).

It contains the important bug fix which happened after Update Rollup 7 which caused the sender of the Delivery Status Notification to be unresolved.

KB 968012 details about the issues fixed in this release of update rollup.

Read more on MSExchange Team Blog.

Exchange Server 2007 SP2... Arriving Soon!

Exchange Server 2007 SP2 is set to arrive in Q3 this year... it contains many new features but some great news on the backup front. It is providing the new backup VSS-based plugin that will enable users to take Exchange aware VSS backups from Windows Server 2008. So we will be able to backup and restore Exchange 2007 SP2 databases from Windows Server 2008 backup tool.

For more details and other features, please read this MSExchange Team blog.

Outlook Anywhere or RPC over HTTPS configuration from Script

I was reading this interesting post from Oz Casey Dedeal about RPC over HTTPS Script. This prompted to me to write this post as i was working on this some time back and had another way of scripting RPC over HTTPS and Outlook Anywhere configuration.

This VB script will do the configuration for both Outlook 2003 and Outlook 2007. This script basically aims at changing the registry entries for your Outlook Profile that do all the outlook over https or outlook anywhere configuration.

Here are the Registry Keys and values that we are targetting at for doing this configuration in an Outlook Profile:

HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows Messaging Subsystem\Profiles\\13dbb0c8aa05101a9bb000aa002fc45a

"00036601" - for Cached Mode
"00036623" - Enable Exchange Proxy settings and control various check boxes like "on fast networks…" etc.
"00036627" - For Authentication - Basic or NTLM
"001f6622" - for specifying Exchange proxy server name
"001f6625" - for specifying Exchange proxy server name according to principal cert name.

So the script will go like:

Const HKEY_CURRENT_USER = &H80000001
strComputer = "."
Set oReg=GetObject("winmgmts:{impersonationLevel=impersonate}!\\" & _
strComputer & "\root\default:StdRegProv")
strValue1Name = "00036601"
arrValue1 = Array(&H00,&H00,&H00,&H00)
strValue2Name = "00036623"
arrValue2 = Array(&H00,&H00,&H00,&H00)
strValue3Name = "00036627"
arrValue3 = Array(&H00,&H00,&H00,&H00)
strValue4Name = "001f6622"
arrValue4 = Array(&H00,&H00,&H00,&H00)
strValue5Name = "001f6625"
arrValue5 = Array(&H00,&H00,&H00,&H00)
strKeyPath = "Software\Microsoft\Windows NT\CurrentVersion\Windows Messaging Subsystem\Profiles"
oReg.EnumKey HKEY_CURRENT_USER, strKeyPath, arrSubKeys

For Each subkey In arrSubKeys
strFullPath = strKeyPath & "\" & subkey & "\13dbb0c8aa05101a9bb000aa002fc45a"
oReg.SetBinaryValue HKEY_CURRENT_USER,strFullPath,strValue1Name,arrValue1
oReg.SetBinaryValue HKEY_CURRENT_USER,strFullPath,strValue2Name,arrValue2
oReg.SetBinaryValue HKEY_CURRENT_USER,strFullPath,strValue3Name,arrValue3
oReg.SetBinaryValue HKEY_CURRENT_USER,strFullPath,strValue4Name,arrValue4
oReg.SetBinaryValue HKEY_CURRENT_USER,strFullPath,strValue5Name,arrValue5
Next

Replace the value of 00 after &H in arrValue1, arrValue2, arrValue3, arrValue4 and arrValue5 with your values by looking into the registry under mentioned reg keys.

Update Rollup 7 for Microsoft Exchange Server SP1 Released

Microsoft has released Update Rollup 7 for Microsoft Exchange Server 2007 Service Pack 1 (SP1).

This update has important fixes for SCR and IMAP4 issues.

KB 960384 details about the issues fixed in this release of update rollup.

Read more on MSExchange Team Blog.

Integration Of Exchange 2007 and OCS 2007

In the last post, I discussed about the Microsoft's core solutions on Unified Communications - Exchange Server 2007 UM and OCS 2007. I had a chance to setup a test environment where they both operate together. So here we will talk about their intergration and take a look how it looks like.

To have both of them work together, you need to have Exchange Server 2007 SP1. Here are the key steps that you need to perform to configure them:

1. Configure the new dial plan. To do this, run this command from the powershell:

   New-umdialplan -name OCSPlan -Uritype "Sipname" -Voipsecurity "SipSecured" -Numberofdigitsinextension 4



2. Go to properties of this dial plan and set the subscriber access number. Subscriber access is used by users to access their individual mailboxes to retrieve e-mail, voice messages, contacts, and calendaring information. Outlook Voice Access is the new Exchange 2007 Unified Messaging feature that lets subscribers access their Exchange 2007 mailbox.


3. Apply this dial plan to the UM server:
   set-umserver -id UM_Server_Name -dialplans OCSPlan


4. Run Powershell script "EXCHUCUTIL.PS1" from Exchange Management Shell. This is installed when you apply SP1 for Exchange 2007. To run this successfully you might need to modify the properties of the Start Menu shortcut for the Exchange Management Shell so that it launches directly from the Scripts folder "Program files\Microsoft\Exchange Server\Scripts".


5. On the OCS server, run OCSumutil with the following command line: ocsumutil /domain:yourdomain.com
   

Now you can configure your users for Unified Messaging. You can do this from Exchange Management Console and right click on the user to Enable Unified Messaging and select the dial plan.

So now when you log on with this user to Communicator 2007, you will see the additional call menu from where you can forward your calls or redirect incoming calls to voicemail.



And now you get a Missed Conversation notification when someone IMs you and you are offline or away:

Also, You get the missed call notifications or voice mails when someone calls you via OCS client:

The world of Unified Communications

Over the recent times, this has been one of the hottest topic of discussion in various organizations and among various professionals.

Microsoft and third-party vendors such as Cisco Systems, Avaya, Nortel, and Polycom offer products that support Unified Communications (UC), and have their own definitions for UC.

If we talk about Microsoft here, Microsoft offers two integrated solutions: Microsoft Exchange Server 2007 and Office Communications Server 2007 that are the key players in Microsoft's UC strategy. Together they bridge the gap between computers and telephones. They integrate with your company's exisiting phone system and deliver complete communication services using your existing data network.

So in the world of Unified Communications, Microsoft offers Exchange as the Unified Messaging component, handling voicemail, fax, and telephone access to messaging. OCS is the component that offers IM, conferencing, presence, and voice services.

Microsoft Exchange Server 2007 Unfied Messaging

Here are the features that Unified Messaging Role provides in Exchange Server 2007:

Outlook Voice Access (OVA): Outlook Voice Access allows a phone to be a Unified Messaging client. A text-to-speech engine is built into the UM server to allow email message to be read from a users mailbox. A UM-enabled user can call into their company's UM server and can access Voicemail, Email, Calendar, Contacts, OOO messages and security and personalization settings.

Call Answering: Say if a user receives any external call, this call will be routed via IP/PBX or a VoIP gateway, if the destination user is not available, this call will be routed to Unified Messaging Server. The external user will be given an option to leave a voice mail and it will be delivered to the mailbox server, else the user will be notified of the missed call.

Auto Attendant: The Auto Attendant in the Exchange Unified Messaging Server allows an organization to create customized menus, custom greetings, searching directory etc.

Fax Receiving: The UM server provides the ability to receive faxes in .tiff format via IP/PBX or VoIP gateway.

Microsoft Office Communications Server 2007

Office Communications Server 2007 manages all real-time (synchronous) communications including: instant messaging, VoIP, audio and video conferencing. It works with existing tele-communications systems, so business can deploy advanced VoIP and conferencing without tearing out their legacy phone networks. Microsoft Office Communications Server 2007 also powers Presence. With presence, you can see at-a-glance if someone is available and contact them with a click using instant messaging, a phone call or a video.

Microsoft unified communications technologies delivers voice and video conferencing through Microsoft Office Communications Server 2007 via IP. This means that conference call audio and video streams are captured and logged just like an instant message or an email.

The complete conferencing solution requires:

• Office Communications Server 2007
• Microsoft Office Communicator 2007
• Microsoft Office Live Meeting service (2007)
• Video-equipped computers and/or VoIP phones

Integration of Exchange 2007 and OCS 2007

Microsoft Exchange Server 2007 Unified Messaging and Microsoft Office Communications Server 2007 can be deployed together to provide voice messaging, Instant Messaging (IM), enhanced user presence, audio-video conferencing, and an integrated e-mail and messaging experience for users in your organization.

Here are the key features and benefits that they will provide together:

• You get the missed call notifications or voice mails when someone calls you via OCS client.
• You get a notification when someone IMs you and you are offline or away.
• OCS automatically uses the out-of-office (OOF) message text you set in Exchange.
• Presence information displayed in Microsoft Outlook 2003/2007 and in Windows Sharepoints Services team sites and document libraries.

So in a nutshell, you are Connected... Always!

Update Rollup 6 for Microsoft Exchange Server SP1 Released

Microsoft has released Update Rollup 6 for Microsoft Exchange Server 2007 Service Pack 1 (SP1).

This update has a fix for the critical security issue and a fix to allow IE 8 to be used for OWA 2007. This does not include OWA 2007 S/MIME control.

KB 959241 details about the issues fixed in this release of update rollup.

Read more on MSExchange Team Blog.

Some mailboxes show up as Shared or Linked... after Migrating to Exchange Server 2007

Here's a scenario where after migrating users from Exchange Server 2003 to Exchange Server 2007, some of the user mailboxes show as "Shared" Mailbox or "Linked" Mailbox within the Exchange Management Console... instead of showing them as "User" Mailbox.

A Linked mailbox is a mailbox that is associated with an external account. Thus Linked mailboxes are normal mailboxes that can hold an External account in a separate resource forest.

Few of these mailboxes here were shown as Linked mailboxes after migration because an orphan Active Directory Account has the "Associated External Account" right on the mailbox in question.

To fix this and have them show up as normal "User" mailboxes remove that orphan Active Directory account that has the "Associated External Account" right on the mailbox in question and run the following command from the Exchange Management Shell:

set-mailbox -id MAILBOX_NAME -ApplyMandatoryProperties

Now we come to why few mailboxes are shown up here as Shared mailboxes. If you have Self permission with associated external account checked, you get the shared mailbox on migration. That is the reason these mailboxes are showed up as shared.

To fix this, remove the "Associated External Account" permission from the Self and again run that command:

set-mailbox -id MAILBOX_NAME -ApplyMandatoryProperties

To read and understand more about the ApplyMandatoryProperties Parameter, read this excellent blog entry from Evan Dodds.

Exchange Server Remote Connectivity Analyzer

This looks pretty exciting... in beta though but worth keeping an eye on as it can be very useful for exchange admins... especially the amount of troubleshooting we need to do... :-)

https://www.testexchangeconnectivity.com/

Entourage for EWS

Entourage for Exchange Web Services is targeted at organizations using Exchange Server 2007. This means that we can finaly say goodbye to WebDav and hopefully to all the issues that we face as EWS is a stronger and more robust protocol than WebDAV, that enables client applications to communicate with the server running Microsoft Exchange Server 2007 SP1 or later – for better compatibility, performance and reliability.

Entourage EWS will launch a public beta this month. The final release will be available later this year as a free update to Office 2008 users.

More Details: http://www.microsoft.com/mac/itpros/entourage-ews.mspx

Configuring Autodiscover for Exchange 2007

The Autodiscover service provides a mechanism to automatically configure Exchange 2007 client applications to access the Client Access server.

It is used to set up client applications like Outlook to work with Exchange by returning configuration data that is necessary for applications to function properly without requiring users to know where to fetch the data, such as discovery of the server that hosts a user's mailbox.

Configuring Autodiscover for External Access

Outlook 2007 tries the following two URLs to try to connect to the Autodiscover service:

https://mydomain.com/autodiscover/autodiscover.xml

https://autodiscover.mydomain.com/autodiscover/autodiscover.xml

Step 1: Configuring DNS

We will discuss the two simple and most commonly used scenarios here:

1. Using a SSL Certificate That Supports Multiple DNS Names
There are third-party Certification Authorities (CAs) that currently support Subject Alternative Names. In this you provide all the necessary DNS names like mail.mydomain.com, autodiscover.mydomain.com etc. in the same certificate by using a Unified Communications certificate that supports the Subject Alternative Name field.

For the Autodiscover service to function correctly, you must add an additional host record (autodiscover.mydomain.com) so that Outlook 2007 clients can locate and connect to the Autodiscover Service when they use the Outlook Anywhere feature from the Internet. The host record you create should map to the Public IP Address that will be used as the entry point to your Client Access server.

2. Using One Single-Name Certificate and the Autodiscover SRV Record
This solution is to use one single-name certificate installed on the Default Web Site.
If your DNS provider supports SRV records, this solution is the simplest and least expensive way to deploy Outlook Anywhere in hosted and non-hosted Exchange 2007 environments.

Create an SRV record:
Service: _autodiscoverProtocol: _tcpPort Number: 443 Host: mail.mydomain.com

For more information on Outlook 2007 and Autodiscover SRV records configuration, please read this knowledgebase article: http://support.microsoft.com/?kbid=940881

Step 2: Modify the Service Connection Point (SCP)

By default, the URL for the Autodiscover Service stored in the SCP object in Active Directory will reference the internal FQDN for the Client Access server during Exchange 2007 Setup. You will use the Set-ClientAccessServer cmdlet to modify this URL so that it points to the new location (FQDN) for the Autodiscover service.

In the Exchange Management Shell, run the following command:

Set-ClientAccessServer -identity CAS_servername -AutodiscoverServiceInternalUri https://mail.mydomain.com/autodiscover/autodiscover.xml

You can point this to https://autodiscover.mydomain.com/autodiscover/autodiscover.xml if you are using DNS host record for autodiscover.mydomain.com.

Step 3: Configuring Exchange Services for Autodiscover

1. Enable Outlook Anywhere for the external host name.

Enable-OutlookAnywhere -Server CAS_servername -ExternalHostname "mail.mydomain.com" -ExternalAuthenticationMethod "Basic" -SSLOffloading:$False

2. Configure the external URL for offline address book for the Autodiscover service.

Set-OABVirtualDirectory -identity "CAS_servername\OAB (Default Web Site)" -externalurl https://mail.mydomain.com/OAB -RequireSSL:$true

3. Configure the external URL for Unified Messaging for the Autodiscover service.

Set-UMVirtualDirectory -identity "CAS_servername\UnifiedMessaging (Default Web Site)" -externalurl https://mail.mydomain.com/UnifiedMessaging/Service.asmx -BasicAuthentication:$True

4. Configure the external URL for Exchange Web Services for the Availability service and Out of Office services.

Set-WebServicesVirtualDirectory -identity "CAS_servername\EWS (Default Web Site)" -externalurl https://mail.mydomain.com/EWS/Exchange.asmx -BasicAuthentication:$True

Update Rollup 5 for Exchange 2007 SP1

The Update Rollup 5 for Exchange 2007 SP1 has been released and is available at Microsoft Download Center.
So would recommend that you should plan for its install as this has fixed quite a lot of issues.
More details at MS Exchange Team Blog.

Information Store Crashing, Exchange 2007

The Microsoft Information Store Service (Store.exe) is repeatedly crashing an Exchange 2007 Mailbox Server.
In the application log, we get the following error message and store.exe is crashing due to EXCDO.DLL file:

Faulting application store.exe, version XXXX, time stamp XXXX, faulting module EXCDO.DLL, version XXXX, time stamp XXXX, exception code XXXX, fault offset 0x00000000001ed390, process id 0x1fc8, application start time XXXX.

Have opened up a case with MS PSS and had them analyze the crash dumps. They have identified it as a Bug. The issue is casued by Mac's, Entourage clients that does calendar bookings in the ICS format and the crash is occuring due to Entourage Client accessing a badly created ICS.
MS will provide a fix to this issue in Update Rollup 6.

If anyone is experiencing this issue, make sure you call MS PSS first thing and have them provide the temp bug fix to you.

Web Services, Exchange 2007

Now that we have finished the final phase of our migration and we have fully migrated the Public Folders to the new Exchange 2007 environment, want to talk about this exciting new component of Exchange 2007, that is the Web Services. Well I think this is the most exciting and amazing new feature in Exchange 2007 that makes life very easy of an Exchange Admin.

The Web Services that are included in Microsoft Exchange Server 2007 provide an XML messaging interface for managing Exchange store items and accessing functionality on a computer that is running Exchange 2007 from client applications.

Exchange 2007 includes the following Web services:

1. Exchange Web Services
2. Autodiscover Service
3. Unified Messaging Web Service

1. Exchange Web Services

Exchange Web Services provides the functionality to enable client applications to communicate with the Exchange server. Exchange Web Services is deployed with the Client Access server (CAS) role. Microsoft Exchange Server 2007 clients connect to the computer that is running Exchange 2007 that has the Client Access server role installed in an Active Directory directory service site by using an HTTPS connection.

Some of the main operations that Exchange Web Services provide are:

• The Availability Service: Outlook 2007 clients can use HTTPS to connect and download free and busy data for other users through the Availability Service. Unlike previous versions of Exchange, free/busy data does not have to be stored in public folders, instead we access the target mailbox’s free/busy data directly from the calendar (via the Availability service).
• OOF: The ability to set Out-Of-Office messages is controlled by a new web service.
• OAB Distribution: Outlook can use HTTPS to locate and download the Offline Address Book (OAB) from a web distribution point.
• The Exchange Data Service operations: The Exchange Data Service operations enable the handling and organizing of items, folders, and attachments, as well as ambiguous name resolution and distribution list expansion.
• Notification and Synchronization Operations.

2. Autodiscover Service

The Autodiscover service provides a mechanism to automatically configure Exchange 2007 client applications to access the Client Access server.

It is used to set up client applications like Outlook to work with Exchange by returning configuration data that is necessary for applications to function properly without requiring users to know where to fetch the data, such as discovery of the server that hosts a user's mailbox.

3. Unified Messaging Web Service

The Unified Messaging Web Service provides an extensibility point for clients to read and change information about Unified Messaging properties. If your mailbox is enabled to use Exchange 2007 Unified Messaging, you can use Outlook 2007 to play a voice message back to a phone.

Will discuss about their configuration in detail in the coming posts :-)

Get HUB server stats from Message Tracking

Now in Exchange 2007, from Command Shell using Message Tracking, you can pull out some of the very exciting statistics which were never so easy from the previous versions of exchange.

Here we are talking about pulling up records like:

• Number of emails sent by HUB servers over a given period of time.
• Number of emails received by HUB servers over a given period of time.
• Number of emails sent by a particular sender or received by a particular recipient over a given period time

Example: To get the number of emails sent by a HUB server, run this command from EMS:

Get-MessageTrackinglog -server -start "MM/DD/YYYY hh:mm am/pm" -End "MM/DD/YYYY hh:mm /pm" -event SEND -ResultSize 999999 I measure-object

Similarly you can add the switches like -event RECEIVE to get the number of message recieved, -Sender "Email address" to get from a particular sender etc.

Read this article from Bharat Suneja to get more details on Message Tracking from Exchange Server 2007

Playing with RSG | Database Restore

This came across few days back when one of our production Exchange 2003 backend server went down due to hardware failure and was totaly dead.The Backup team was shortly in action to carry out the restore. The restore was done on the different server in a Recovery Storage Group (RSG).

Now the question is how to merge these mailboxes in RSG with the production ones... certainly direct merge was not possible as we didnt opt for Dialtone method as the production server was totaly dead and we didnt set up a new server to replace that one.

The one option was to to extract the mailboxes from RSG using Exmerge, delete the existing mailboxes of users and create new ones on another server, and then import that extracted mailboxes. But this is very time consuming.
However here's an another option to tweak the RSG to make it behave as the production store and move that mailboxes over.

The Recovery Storage Group is identified by the msExchRestore Attribute. The msExchRestore = TRUE property tells us if a database is a recovery database.
As such we cannot directly connect the mailbox from the RSG to user direcly. We have to modify this msExchRestore Attribute and make its value to Not Set so that it cannot be identified as RSG and we can connect the mailbox to the user.

The detailed steps are as follows:

1. Reset the MsExchRestore attribute on both the Recovery Storage Group, and the recovered mailbox store using Adsiedit:

Expand the Configuration Container node, and then browse the hierarchy to:
DC=Domain
DC=com
CN=Configuration
CN=Services
CN=Microsoft Exchange
CN=Administrative Groups
CN=Administrative Group Name
CN=Servers
CN=ExchangeServerName
CN=InformationStore
CN=Recovery Storage Group

Right click for Properties on the Recovery Storage Group, ensure that the checkbox for "Show Optional Attributes" is checked. Scroll down to the "MsExchRestore" attribute. Double-click the MsExchRestore attribute and check the Not Set parameter. Click OK, Apply, and OK to exit the properties pane.
Right click the "CN=MailBox Store(ServerName)" under the Recovery Storage Group, and select Properties. Ensure that the checkbox for "Show Optional Attributes" is checked. Scroll down to the "MsExchRestore" attribute. Double-click the MsExchRestore attribute and check the parameter. Click OK, Apply, and OK to exit the properties pane.
Close the AdsiEdit mmc

2. Now from the ADUC>Exchange Tasks, delete the mailboxes of the users that are in question.

3. In Exchange System Manager select the Recovery Storage Group, right click and select Refresh. Expand the Recovery Storage Group, then the mailbox store.

4. Select "Mailboxes" under the Mailbox Store, then right click the mailbox to be recovered, and select "Reconnect". The applet "Select a New User for this Mailbox" applet will appear. Enter the alias of the user you wish to associate with the recovered mailbox into the "Enter the Object Name to select" data entry field, the click "Check Name". The alias of the user should be resolved to the full display name. Click OK. You will see a pop-up stating "The operation has completed successfully".

5. Once its done for all the users, you can successfully move the mailboxes over to any of the servers.

IMAP not working for users | Mailbox server in different AD site than CAS

Here we have a cross site scenario where users from one site are trying to connect to the CAS that is on the different site.

By default, POP3 and IMAP4 connectivity between a Client Access server in one Active Directory site and a Mailbox server in another Active Directory site is not enabled. The Client Access server prevents users from logging on to their mailboxes by using POP3 or IMAP4 if their mailboxes are located on a Mailbox server in a different Active Directory site.

And we get the following warning in the application log of the Client Access Server:

User "User-Name" was prevented connecting to his/her mailbox because the Mailbox Server resides in a different ActiveDirectory site (CN=Site A,CN=Sites,CN=Configuration,DC=domain,DC=com) than the Client Access Server (CN=Site B,CN=Sites,CN=Configuration,DC=domain,DC=com) to which he/she connected. Either arrange for the Client Access Server and the Mailbox Server to reside in the same site, or change the configuration setting of AllowCrossSiteSessions to true.

To enable cross-site connectivity for POP3 and IMAP4 clients:

1. On the Client Access server, locate the POP3 and IMAP4 configuration files. By default, the location is C:\Program Files\Microsoft\Exchange Server\ClientAccess\PopImap.
2. Use the text editor to open the configuration files. The two configuration files are as follows:
   Microsoft.Exchange.Pop3.exe.Config
   Microsoft.Exchange.Imap4.exe.Config
3. Search for the key AllowCrossSiteSessions. add key="AllowCrossSiteSessions" value="false" /
4. Edit the line of the configuration file as follows. add key="AllowCrossSiteSessions" value="true" /
5. Repeat the steps in this procedure for each protocol for which you want to enable cross-site connectivity.
6. Restart the services for each configuration file that you have updated to enable cross-site connectivity.

More Details at Microsoft Technet.

500 Internal Server Error when using OWA with /Exchange

You get this 500 - Internal Server error while you access Outlook Web Access from https://CASServer.domainname.com/exchange while https://CASServer.domainname.com/owa works fine.
This happens when you have seperate Exchange 2007 Mailbox and CAS servers. Ideally the request should be redirecetd to /owa but you get 500 - Internal Server Error right after typing in your credentials in the forms login page.

This happens due to the fact that redirection is not working because ISAPI Extensions are not installed on the Mailbox Server. ISAPI extensions handle specific incoming requests to the IIS server. Extensions are loaded when they are first needed and kept in memory until the host process shuts down.

To fix this issue, please install the ISAPI Extensions on the mailbox server.

Here is the command that you have to run from the EMS to install them:

ServerManagerCmd -i Web-ISAPI-Ext

Make sure to do an IISRESET after this.

Storage Group not responding | Version Store Issues

This happend few days earlier on our exchange server... all users in a particular Storage Group were not able to connect to Outlook/OWA. The mails queued up for them on the server...
On looking at the server logs... there were lot of logon error messages... users were not able to logon to their mailbox... and at the beginning when it all started, there was one error message with Event Id 623. It says:

Information Store (2984) Storage Group 1: The version store for this instance (3) has reached its maximum size of 155MB. It is likely that a long running transaction is preventing cleanup of the version store and causing it to build up in size. Updates will be rejected until long-running transaction has been completely committed or rolled back.

Analysis

The Version Store keeps an in-memory list of modifications made to the database. It gives ESE the ability to track and manage the current transactions. Thus the Version Store is where transactions are held in memory until they can be written to disk.

Event 623 is the result, typically of a long running transaction. The result of this long running transaction is to exhaust resources in the version store. As a result, the Version Store no longer reaps deleted records causing unneeded data, which is marked as deleted, to accumulate in the database. The accumulation of unneeded data can exacerbate performance problems which can lead to event id 623. No more transaction can continue until this is clear.

Thus we will see 623 event indicating that the maximum Version Store size has been reached . All the Write operations to the database will fail because there's no more version store space to record the operation.

Why this happens

This can happen for one of the two reasons:

1) In order to properly reconcile write-conflicts and properly support repeatable reads, a given entry in the version store cannot be cleaned up until it is older that the oldest active transaction.
2) Version Store cleanup simply cant keep up with the load on the machine.

Possible Causes

- Online Maintenance Tasks running at peak times.
- Backups running at peak times.
- Disk I/O performance.
- Large Mails

Any of these can add up simultaneously and add to the performance degrade of the server.

More details and troubleshooting on this.

Useful Exchange Management Shell Cmdlets

Convert a legacy Exchange 2003 "resource" into a room mailbox in Exchange 2007

Move the mailbox to an Exchange 2007 server
Run: set-mailbox [MailboxName] –type Room
Then run: set-mailboxcalendarsettings [MailboxName] –AutomateProcessing AutoAccept

Configure the conference room resource mailboxes to remove attached files from meeting requests

Get-Mailbox - RecipientTypeDetails RoomMailbox Set-MailboxCalendarSettings -DeleteAttachments:$true

Get a list of Exchange ActiveSync users

$mbx = get-casmailbox where {$_.hasactivesyncdevicepartnership -eq $true -and $_.identity -notlike "*CAS_{*"} ; $mbx foreach {$name = $_.name; $device = get-activesync devicestatistics -mailbox $_.identity; $device foreach {write-host $mbx.name, $_.devicemodel, $_.devicephonenumber, $_.deviceid, $_.FirstSyncTime, $_.LastSuccessSync} }

Get details of single EAS mailbox

Get-ActivesyncDeviceStatistics -mailbox user@domain.com

An inappropriate message that has the subject line of exchange is sent to all users on the Exchange server 2007 mailbox server named Exch1. You need to delete this message from all the mailboxes.

Create a new mailbox named TempMailbox that has a folder named Export. Run the Get-Mailbox -Server Exch1 Export-Mailbox -TargetMailbox TempMailbox -TargetFolder Export -SubjectKeywords "Exchange" -DeleteContent cmdlet.

Get list of all user mailboxes with a list of email addresses attached to each user.

get-mailbox select-object name, alias, primarySmtpAddress Export-Csv C:\mailboxes.csv -NoTypeInformation

Generic User Accounts | Exchange 2007 Shared Mailboxes

In an organization, there are mailboxes required that are shared by many individuals in a particular department... I will say them as generic accounts that a group of people use for common mail access. However, the Information Security team may take it as offensive as they have an active mailbox enabled user account... and if you decide to close on them, it becomes really difficult as users are used to them as it helps them to organize and manage their tasks efficiently... and instead creating the Distribution List with the same email address won't solve the purpose.

In Exchange 2007, we have concept of shared mailbox recipient type. When we create a mailbox as 'shared' it creates a disabled active directory account to which the mailbox is connected. Shared mailboxes do not have an associated password so we must grant mailbox permissions for the users requiring access to that mailbox.

Advantages

• Disabled accounts act as a security measure.
• Since the user account is disabled by default no initial password is required.
• If desired, existing mailboxes can be converted to shared mailboxes. Users can still be able to access emails and continue to receive emails on that mailbox.
• Will let the users to continue their operations more or less the same way.
• No need to setup Distributions Lists on account of closure of their respective generic accounts.

Public Folder database dismounted after you move all the Public Folder Replicas from Exchange 2003 server to Exchange 2007 server

Issue with Public Folders

It has been observered that when we decommision the Exchange 2003 server after moving all the Public Folders Replicas from it to the Exchange 2007 Server, the Outlook stops connecting for all the clients... Public folders doesn't show anything from Outlook Web Access and even Public Folder Management Console on Exchange 2007 server doesnt show any of the Public Folders and the Public Folder database doesnt mount.

This typically happens when we manually remove the Exchange 2003 server hosting earlier all the Public Folder replicas.

This happens because the msExchOwningPFTree attribute had its value missing. This msExchOwningPFTree attribute controls the Public Folder database path and contains a list of all the stores in the hierarchy.

We need to specify its correct value in order to make Public Folders work. We can do it from ADSI Edit tool.

• Start the ADSI Edit tool
• Expand the Configuration container, then expand out each container as follows: CN=Services then CN=Microsoft Exchange then CN=YourExchangeOrg then CN=Administrative Groups then CN=AdminGroupofyourPFServer then CN=Servers then CN=YourPFServer then CN=InformationStore and then click on CN=StorageGroupContainingYourPFStore. In the pane on the right you see the public store object listed. Right click on the object and click on properties.
• In the list of attributes, double click on the msExchOwningPFTree attribute and specify the correct value.
• Restart Microsoft Exchange Information Store service.

Here is the Microsoft KB article that will help you to determine the correct value of msExchOwningPFTree attribute and set that up.

Find Users not using Default Exchange Storage Limit set via Mailbox Policy

Here's an LDAP query that I use frequently to search and display all the users in the domain that do not have the default mailbox store policy set.

(&((mailNickname=*)(mDBUseDefaults=FALSE)))

Windows update available that will turn off the SNP

There is a new High Priority Windows update available that will turn off the Scalable Networking Pack features which are installed by default in Windows 2003 SP 2.
http://msexchangeteam.com/archive/2008/03/12/448421.aspx
You have to reboot the server after applying this update.