Released: Exchange Server 2013 RTM Cumulative Update 1

Published Apr 02 2013 09:00 AM 99K Views

We know a lot of you have been waiting for this, and so it is with great excitement that we announce that Exchange Server 2013 RTM Cumulative Update 1 (CU1) has been released to the web and is available for immediate download! This is the first release using the new servicing model for Exchange Server 2013. In addition to this article, the Exchange 2013 RTM CU1 release notes are also available.

Note: Article links that may not have been available at the time of this post's publishing are now available. Updated Exchange 2013 documentation, including Release Notes, is now available on TechNet.

CU1 is the minimum version of Exchange 2013 required for on-premises coexistence with supported legacy Exchange Server versions. The final build number for CU1 is 15.0.620.29. For more information on coexistence, check out the Planning and Deployment documentation, and this Ignite webcast covering deployment of and coexistence with Exchange Server 2013.

Upgrading/Deploying Cumulative Update 1

Unlike previous versions, cumulative updates do not use the rollup infrastructure; cumulative updates are actually full builds of the product, meaning that when you want to deploy a new server, you simply use the latest cumulative update build available and do not necessarily need to apply additional Exchange Server updates.

Active Directory Preparation

Prior to upgrading or deploying the new build onto a server, you will need to update Active Directory. For those of you with a diverse Active Directory permissions model you will want to perform the following steps:

  1. Exchange 2013 RTM CU1 includes schema changes. Therefore, you will need to execute setup.exe /PrepareSchema /IAcceptExchangeServerLicenseTerms.
  2. Exchange 2013 RTM CU1 includes enterprise Active Directory changes (e.g., RBAC roles have been updated to support new cmdlets and/or properties). Therefore, you will need to execute setup.exe /PrepareAD /IAcceptExchangeServerLicenseTerms.
  3. Exchange 2013 RTM CU1 includes changes to the permissions within the domain partition (e.g., Exchange Servers have been granted the ability to modify msExchActiveSyncDevices class on inetOrgPerson objects). Therefore, you will need to execute setup.exe /PrepareDomain /IAcceptExchangeServerLicenseTerms in each domain containing Exchange servers or mailboxes.
Note: If your environment contains only Exchange 2007, and you upgrade to Exchange 2013, keep in mind you cannot deploy Exchange 2010 in that environment at a later time. If you foresee a need to deploy Exchange 2010 servers into your environment, deploy an Exchange 2010 multi-role server (with all four servers roles) prior to executing Exchange 2013 setup.exe /PrepareAD. As long as you retain at least one role of each legacy server, you will continue to be able to install additional servers of that version into your coexistence environment. Once you remove the last server role of a legacy version, you will no longer be able to reintroduce that version into the environment.

Coexistence Pre-Deployment Step: OAB Verification

As mentioned in the Exchange Server 2013 CU1 release notes, when you deploy the first Exchange 2013 Mailbox server in an existing Exchange organization, a new default Offline Address Book is created.

Figure 1: The new OAB as shown in an Exchange Server 2010 SP3 & 2013 CU1 environment

All existing clients that rely on an OAB will see this new default OAB the next time they look for an OAB update. This will cause these clients to perform a full OAB download. To prevent this from happening, you can configure your existing mailbox databases to explicitly point to the current default OAB prior to introducing the first Exchange 2013 server. You can do this one of two ways:

  1. Within the Exchange Management Console (EMC), navigate to Organization Configuration –> Mailbox –> Database Management –> Mailbox Database Properties –> Client Settings.

    Figure 2: Modifying the default Offline Address Book at the database level in the EMC

  2. Alternatively, if you have many mailbox databases to update, the following Exchange Management Shell command can be used to view all mailbox databases without a default OAB explicitly set on them. If you have both Exchange 2007 and Exchange 2010 deployed on-premises then you will have to run the following commands using the respective Exchange Management Shell version as the Get/Set-MailboxDatabase commands are version specific.

    Get-MailboxDatabase | Where {$_.OfflineAddressBook -eq $Null} | FT Name,OfflineAddressBook -AutoSize

    If no values are returned then you are already prepared. However, if you need to configure some databases, then this next command will find all mailbox databases in an Exchange 2007 or Exchange 2010 environment with no default OAB defined at the database level, and it will set it to the current default OAB in the org.

    Get-MailboxDatabase | Where {$_.OfflineAddressBook -eq $Null} | Set-MailboxDatabase -OfflineAddressBook (Get-OfflineAddressBook | Where {$_.IsDefault -eq $True})

    To confirm all Exchange 2007/2010 mailbox databases now have a defined default OAB, re-run the first command. This time it should return no entries.

Server Deployment

Once the preparatory steps are completed, you can then deploy CU1 and start your coexistence journey. If this is your first Exchange 2013 server deployment, you will need to deploy both an Exchange 2013 Client Access Server and an Exchange 2013 Mailbox Server into the organization. As explained in Exchange 2013 Client Access Server Role, CAS 2013 is simply an authentication and proxy/redirection server; all data processing (including the execution of remote PowerShell cmdlets) occurs on the Mailbox server. You can either deploy a multi-role server or each role separately (just remember if you deploy them separately, you cannot manage the Exchange 2013 environment until you install both roles).

If you already deployed Exchange 2013 RTM code and want to upgrade to CU1, you will run setup.exe /m:upgrade /IAcceptExchangeServerLicenseTerms from a command line after completing the Active Directory preparatory steps or run through the GUI installer. Deploying future cumulative updates will operate in the same manner.

Note: Unlike previous versions, in Exchange 2013, you cannot uninstall a single role from a multi-role server. For example, if you deploy the CAS and MBX roles on a single machine, you cannot later execute setup to remove the CAS role; you can only uninstall all server roles.

Mailbox Sizes in Exchange Server 2013

As you start migrating your mailboxes to Exchange 2013, one thing you may notice is that your mailboxes appear to be larger post move.

As you can imagine, with hosting millions of mailboxes in Office 365, accurate storage reporting is essential, just like in your on-premises deployments. One of the learnings that we accrued into the on-premises product is ensuring that the mailbox usage statistics are more closely aligned with the capacity usage within the Mailbox database. The impact of reporting space more accurately means that mailbox quota limits may need to be adjusted prior to the mailbox move so that users are not locked out of their mailbox during the migration process.

Our improved space calculations may result in a mailbox’s reported size increasing on average of 30% when the mailbox is moved from a legacy version of Exchange to Exchange 2013. For example, if a mailbox is reported as 10GB in size on Exchange Server 2010, then when the mailbox is moved to Exchange 2013, it may be reported as 13GB. This does not mean that migrating to Exchange 2013 will increase your capacity footprint by 30% per mailbox; it only means that the statistics are including more data about the space the mailbox consumes. 30% is an average value, based on what we have experienced in Exchange Online. Customers with pilot mailboxes should determine what their own average increase value may be as some environments may see higher or lower values depending on the most prevalent type of email within their mailboxes. Again, this does not mean there will be an increase in the size of the database file on disk; only the attribution of space to each mailbox will increase.

New Functionality Included in Cumulative Update 1

Exchange 2013 RTM CU1 includes a number of bug fixes and enhancements over the RTM release of Exchange 2013. Some of the more notable enhancements are identified below.

Address Book Policies

As discussed recently, an Address Book Policy Routing Agent has been included in Exchange 2013 RTM CU1. For all the juicy details, see Address Book Policies, Jamba Jokes and Secret Agents.

Groups can once again manage groups!

In Exchange 2010 you could not use a group as an owner for another group for membership management. Instead you had to deploy explicit permissions on groups or use a script as a workaround.

Since Exchange 2010’s release both Microsoft Support and the Exchange Product Group received resounding feedback on the need for this capability. The good news is that with Exchange 2013 RTM CU1 groups can once again be owners of groups for membership management.

Public Folder Favorites Access through Outlook Web App

In Exchange Server 2013 RTM there was no way to access Public Folder content through Outlook Web App. In CU1 you will now have access to Public Folders you have added as favorites via your favorites menu either in Outlook or Outlook Web App. However, this access is limited to Public Folders stored on Exchange Server 2013.

Figure 3: Adding a Public Folder as a favorite in Outlook Web App in Exchange Server 2013 RTM CU1

Remember, you cannot start creating Public Folders on Exchange Server 2013 until all users have been migrated to Exchange Server 2013. For how to migrate from legacy Public Folders to Exchange Server 2013 Public Folders, see Migrate Public Folders to Exchange 2013 From Previous Versions.

Exchange Admin Center Enhancements

The Exchange Admin Center (EAC) has been enhanced and now includes Unified Messaging management, improvements in the migration UI allowing more migration options reducing the gap between PowerShell and the UI, and general overall improvements in the user experience for consistency and simplification based on customer feedback.

High Availability and Monitoring Enhancements

There are have been several enhancements in the high availability and Managed Availability space. In particular:

  • The Best Copy Selection algorithm now honors MaximumActiveDatabases.
  • Auto-reseed now supports disks that have Bitlocker encryption.
  • Many probes, monitors, and responders have been updated and improved over the RTM release.
  • Get-HealthReport cmdlet has been streamlined and its performance has been optimized.
  • Exchange 2013 RTM CU1 will support the Exchange Server 2013 Management Pack for System Center Operations Manager (SCOM); this management pack will be available at a later date. This management pack is supported on SCOM 2007 R2 and SCOM 2012.

On behalf of the Exchange Product Group, thanks again for your continued support and patience, and please keep the feedback coming.

Exchange Team


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Whoa big download! In before anyone else!!

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Nice work, team!  Looking forward to booking some of these upgrade engagements now.  #IamMEC

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Welcome CU1....Thanks Exchange team!!

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Good news. You finally made it.

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Co-existence finally its cool - Thanks for this one :)

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Right on time as promised. Kudos to the Exchange Team !!!

Let the Deployments BEGIN!!!

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Could the file name of the download be a little more descriptive? I know we can change it manually of course, but downloading "Exchange-x64.exe" seems a little too... generic.

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Great work, thanks Exchange team.

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Great work!!!

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Thanks Exchange Team!!!

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Nice work guys!

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Nice work Exchange Team!

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Finally it is here! Thank you Microsoft.

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How can we tell which version this is? The file just shows "Exchange-x64.exe". Are all CU updates going to just have the EXE and we'll need to determine versioning by date?

Other than that, THANK YOU!

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Flood gates are open for Deployments/Migrations. At least the first set. There will be another when SP1 comes out.

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Great work, team!

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Is there an RSS feed for KB articles for Exchange 2013?  I don't see one listed there?

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Great work, Exchange team! :)

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Great work, all! Looking forward to a lot of deployments ;)

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Thanks for the update!  The release notes hit a few of the high points but is there a bug fix list anywhere?

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Be aware, Exchange 2013 RTM CU1 setup stops the transport service during the prerequisite check on upgrades from RTM.  See

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Thanks Exchange Team, your world-wide Exchange On-Premises customers are happy now. And they can upgrade from Ex 2007 or Ex 2010 to Exchange 2013 On-Premises now :)

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As an Exchange On-Premises customer, this is a great news.

We look forward to upgrading to Exchange 2013 On-Premises.

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@Entegy & @Charlie - thanks for the feedback, we will consider a better naming convention moving forward with future cumulative update releases.


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Delivered and packaged ... nice work Team Exchange!

... only leaves one item for me - MAPI/CDO for Ex2013 for Doc level protection.

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For a new deployment do I need to download and install the RTM version first and upgrade or can I just use this download to install 2013? The version showing up in my MSDN is still the RTM version.

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@Vince, as mentioned in the blog CUs are full builds so you can start right with this build. No need to prepare & install RTM and then upgrade to RTM CU1. You can start right with the CU1 bits.

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I'm getting performance counters errors after installing. Errors like this:

Performance counter updating error. Counter name is Current Connected Sessions, category name is MSExchangeRemotePowershell. Optional code: 3. Exception: The exception thrown is : System.InvalidOperationException: The requested Performance Counter is not a custom counter, it has to be initialized as ReadOnly.

  at System.Diagnostics.PerformanceCounter.InitializeImpl()

  at System.Diagnostics.PerformanceCounter.get_RawValue()

  at Microsoft.Exchange.Diagnostics.ExPerformanceCounter.set_RawValue(Int64 value)

Last worker process info : System.ArgumentException: Process with an Id of 12248 is not running.

  at System.Diagnostics.Process.GetProcessById(Int32 processId)

  at Microsoft.Exchange.Diagnostics.ExPerformanceCounter.GetLastWorkerProcessInfo()

Processes running while Performance counter failed to update:

<process list>

Performance Counters Layout information: FileMappingNotFoundException for category MSExchangeRemotePowershell : Microsoft.Exchange.Diagnostics.FileMappingNotFoundException: Cound not open File mapping for name Globalnetfxcustomperfcounters.1.0msexchangeremotepowershell. Error Details: 2

  at Microsoft.Exchange.Diagnostics.FileMapping.OpenFileMapping(String name, Boolean writable)

  at Microsoft.Exchange.Diagnostics.PerformanceCounterMemoryMappedFile.Initialize(String fileMappingName, Boolean writable)

  at Microsoft.Exchange.Diagnostics.ExPerformanceCounter.GetAllInstancesLayout(String categoryName)

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Congrats to the team.  Excited to see this work!

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Thanks Brian, just was a little confused since the original RTM file is almost 4gb and the new update was only 1.3gb

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Thumbs up!

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CU1 installation has broken the lync2013 owa integration :(

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World-Wide Exchange On-Premises customers get ready to upgrade from Ex 2007 or Ex 2010.

We are planning it now :) Thanks Exchange Team.

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Great work everyone! It was worth the wait.

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Sorted it. It takes 2 x reboots of the CAS after install.

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A little confused about the OAB mention above.  We have multiple OABs, each attached to their respective ABPs.  How will these be affected by the new 2013 default OAB?  What is the timeframe for a fix for the ABP/room mbx issue highlighted in the release notes?

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I had been struggling with too many problems previous release for a few days.

Today I downloaded, installed and tested, that one is working. Good job guys!

Please don't release again before test a software properly like in previous release...

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Chris: New MAPICDO here:

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No Sender Based routing?

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good.. at-last cu1 came out...

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Or shall we say, finally E2013 RTM is out ;)

Great work team! Hope all goes fine now....

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Shame the TechNet documentation isn't updated to reflect CU1 coexistence with Exchange 2010.

Any ideas when TechNet will be updated? Otherwise great job.

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When will we see the Technet documentation upgraded to reflect co-existence and upgrade scenarios? Until we have that, CU1 is not much help.

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@SteveT & @And Still No Upgrade Guidance  - TechNet content refresh will go live later today.


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Looking for some guidance on how to properly redirect OWA from HTTP to HTTPS. I see new VDirs, so not sure exactly how to set this. Any documentation on how to do this properly with 2013 now? Very glad to see this CU1 released. Good job.

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After Exchange 2013 CU1 I cannot move mailbox from Exchange 2013 CU1 to Exchange 2010. Error is "stalledduetomailboxlock" - any suggestion. How can I contact technical team Exchange assistance by email or phone?

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NICE - Now on to migrating folks from 2007/2010 to 2013!

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FYI - Documentation is up!  Thanks MS!

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We just finished a CU1 deploy at a greenfield site (sole Exchange 2013 RTM).

Happy to report that once we figured out the prerequisites needed on Server 2012, running the AD prep steps, and then CU1 itself that our Exchange 2013 RTM to CU1 update was successful.

We are now getting some weirdness in the Event Logs such as service failure and restart attempts with (service already started) on MS Exchange RPC Client Access Service. Exchange Search Service seems to be crashing, and then we are getting MSExchangeFASTSearch exception errors.

While the above seems to have been introduced with CU1, the fact that OWA now performs a LOT better than before and MIME based PDF attachments via copiers are no longer killed has brought some happiness to our client! :)


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All we need now is the 2013 Storage Calculator.

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‎Jul 01 2019 04:12 PM
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