DO NOT install patch KB974571 for OCS R2

This patch will break OCS R2

By Alex Lewis on Wed, 10/14/09 - 1:02pm.

As posted first this morning by Doug Deittrick and TomL, aka LCSKid, there is an issue with the patch associated with KB974571. The patch is supposed to resolve a security issue with the Windows CryptoAPI. However, it has the side effect of making OCS R2 think that it is only the eval version and is expired. On reboot the OCS services will not start and OCS will be completely down.

From Doug's blog post with all the information:

Currently an issue is being observed after applying KB974571 (MS09-056: Vulnerabilities in CryptoAPI could allow spoofing) to LCS/OCS servers, that is causing them to believe that they are running an evaluation version of LCS/OCS and that it has expired.

http://support.microsoft.com/kb/974571/

If you apply the patch, the LCS/OCS services fail to start and you see these errors in the event log:

Event Type:        Error
Event Source:    Live Communications Server
Event Category:                (1000)
Event ID:              12290
Date:                     10/13/2009
Time:                     8:28:57 PM
User:                     N/A
Computer:
Description:
The evaluation period for Microsoft Office Live Communication Server 2005 has expired. Obtain the released version of this product and upgrade to the non-evaluation version by running setup.exe

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

Event Type:        Error
Event Source:    Live Communications Server
Event Category:                (1000)
Event ID:              16417
Date:                     10/13/2009
Time:                     8:28:57 PM
User:                     N/A
Computer:
Description:
Unable to initialize the protocol stack. The service has to stop.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

Event Type:        Error
Event Source:    Live Communications Server
Event Category:                (1000)
Event ID:              12299
Date:                     10/13/2009
Time:                     8:28:57 PM
User:                     N/A
Computer:
Description:
The service is shutting down due to an internal error.

Error Code: 0xC3ED0804.
Resolution:
Check the previous event log entries and resolve them. Restart the server. If the problem persists contact product support.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

Uninstalling the patch is the only way to currently fix this issue.

The issue is currently being escalated, but until a fix can be found, delaying the install of KB974571 is recommended.