3/4/14: Blog Post: Known Issues with 2013 SP1
12/4 Update: Added Known Issues list at the end

Today, after a few delays, both Exchange 2010 SP3 RU3 and Exchange 2013 RTM CU3 have been release! For more details on CU3 and a bit of a backstory on this release and the general quality issues Microsoft has had with Exchange recently see Tony Redmon’s post here: http://windowsitpro.com/blog/seeking-quality-exchange-2013-cu3

Exchange 2010 SP3 RU3: Download | KB2891587 | EHLO Blog Post
Exchange 2013 RTM CU3: Download | KB2892464 | EHLO Blog Post

I haven’t seen much about what updates are in 2010 SP3 RU3, but when I do find them I will update this blog.

For Exchange 2013 RU3 there are several key updates:

• AD schema updates (so plan accordingly)
• Addresses issues with 3rd party backup software, see KB2888315 for more details
• Windows 8.1/IE11 no longer require the use of OWA Light
• Usability improvements when adding members to new and existing groups in the Exchange Administration Console
• Online RMS available for use by non-cloud based Exchange deployments
• Improved admin audit log experience

The What’s New in Exchange Server 2013 and Release Notes should also be updated shortly to reflect changes in 2013 RTM CU3.

Note: Make sure you set PowerShell execution policy to “Unrestricted” before installing 2013 RU3, see KB981474 for details and steps.

Microsoft has also publicly stated that the next update to Exchange 2013 will be SP1 in early 2014 (aka as CU4). SP1 will provide Windows 2012 R2 support, S/MIME support in OWA, Edge Transport Server Role, and the various fixes and improvements expected in a SP. The Exchange Team also posted this EHLO blog: Exchange Server: The Road Ahead to dispel any myths that there won’t be an E16 or higher on-premise version.

•  CU are basically a Service Pack that may include new features, but those features may not be documented. CU & SPs for Exchange 2013 are FULL installs, or in-place upgrades, with no un-install support. So make sure you test the CU2 BEFORE installing them in production. Microsoft is calling CU4 a “Service Pack” because this is the first time they are documenting new features and changes that were in the previous CUs. In addition, there are lifecycle requirements tied to “Service Pack” updates.

Reminder:  Customers in hybrid deployments where Exchange is deployed in-house and in the cloud, or who are using Exchange Online Archiving with their in-house Exchange deployment are required to maintain currency on Cumulative Update releases

Known Issues
Like before this is the list of issue I AM aware of, not an official list from  Microsoft. For my previous known issues with Exchange 2013 CU2 see: https://blog.jasonsherry.net/2013/07/09/exchange-2013-rtm-cu2-released/. I’ll add more details and linked to Technet Forums and KBs later this week. Comment on any issues you have come across that you are pretty sure is a bug based on others having the same issue, please include a link to TechNet forums post on the topic.

• I need to review my CU2 issues list and check which of these issues CU3 resolves. On my to-do list 🙂

1. Critical: 12/4 Outlook (all version) on Windows XP cannot access Exchange 2013 CU3 modern Public Folders, when their mailbox is on 2013 CU3 server
   • Only critical if you have Windows XP clients, which many organizations still do
   • Workaround: Have users use OWA or W7+ workstation
2. Important: 12/4 Availability (Free/Busy) and OOF not working after installing KB2837618 or KB2825677 for mailboxes on Exchange 2007 in Outlook 2013
   •  The November Outlook 2013 KB2837618 security update, also in OL13 Oct update KB2825677 breaks Outlook 2013 if the user’s mailbox is on Exchange 2007
     • This issue is new to CU3
     • KB2825677 is now in Windows Update, so if you have Exchange 2007 you need to remove this update!
     • Users will see “Your automatic reply settings cannot be displayed because the server is currently unavailable. Try again later” error message when they click on their Automatic Replies (Out of Office) button.
       • See the “Known issues with this security update” in http://support.microsoft.com/kb/2837618 for more details
   • Workaround: Remove updates and recreate Outlook profile, just removing the update doesn’t fix the issue
3. Important: 12/4 Severe performance problems with IE8 and FF24 on Windows XP
   • Again only important if you have XP clients
   • Seems to be an issue with memory leaks in JavaScript on Windows XP.
     • See Tony Redmond’s blog post on this issue here:
       http://windowsitpro.com/blog/exchange-2013-cu3-causes-headaches-owa-windows-xp
4. Important: 12/4 EAS proxy breaks after EAS App Pool crashes repeatedly
   • This is an issue with Exchange 2013 (RTM – CU3) when it is proxying EAS traffic to Exchange 2007 or 2010 based mailboxes
   • You will see Event ID 4999 | Error | MSExchange Common | With “Watson reported…” in the details
   • I’ve seen this issue at two clients, who were migrating from 2007 to 2013. In both cases users weren’t noticing any issues.
     • After migrating the last mailboxes to 2013 these errors went away
5. Moderate: 12/4 EAS ExternalURL & InternalURLs for EAS are cleaned after installing CU3
   • This has been an issue since 2010 when doing a recovery operation and when installing 2013 CU1 and higher. I don’t recall which URLs are wiped but as a standard policy I create a “Set-URLs.ps1” script that I run after installing the CUs, and on initial setup
     • See Jeff Guillet’s post for more details on the history of this issue: bit.ly/1jmOg4l
   • Workaround: Reset them
     • CU1 & CU2 also cleared the OWA & ECP URLs, so at least those were fixed in CU3
6. Minor: 12/4 Certificate based authentication not working
   • Only an issue for organizations using client certificates for authentication
   • Workaround: Increase uploadReadAheadSize from 0 to 49152 then restart MSExchangeSyncAppPool
     • See this BlackBerry article for more details
   • IIS Logs will contain a 413 error
   • Related Threads
     • Blackberry.com: http://bit.ly/IL3GRG
     • Blackberry.com: http://bit.ly/18bJsw6
     • TechNet.microsoft.com: http://bit.ly/1gaE6nM
7. Minor: 4/2/13 Exchange XML application configuration files are overwritten during cumulative update installation
   • Any customized per-server settings you make in Exchange XML application configuration files, for example, web.config files on Client Access servers or the EdgeTransport.exe.config file on Mailbox servers, will be overwritten when you install an Exchange Cumulative Update (CU). Make sure that you save this information so you can easily re-configure your server after the install. You must re-configure these settings after you install an Exchange CU.
   • From Release notes page