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Does anybody know whether the Office Communications Server 2007 (R2) ist compatible with Windows Server 2008 R2?

I have tried to migrate the 2008 Server to R2 but since then some of the OCS Services won't start up. At the moment I migrated the Edge Server. The only service that did start up is the WebConferencing service. All of the others are claiming about a NullReference Exception while starting up:


A/V Authentication Edge Service could not be started.

Exception: System.NullReferenceException:

Object reference not set to an instance of an object.

at Microsoft.Rtc.MRAS.Core..ctor(ServiceStopHandler serviceStop)

at Microsoft.Rtc.MRAS.Server.OnStart()

Cause: Internal error.

It seems to me that OCS wont work until Microsoft provides a patch since the services appear to have some references that do not exist anymore in 2008 R2.

Has anybody information about a workaround or a MS statement concerning this?

Thanks in advance!

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This error has nothing to do with Desktop Experience - A/V Auth doesn't use that at all; in fact, I'm pretty darn sure the Edge server wouldn't use it at all. As far as official Microsoft statements go, their line would be that OCS 2007 R2 is not supported on Server 2008 R2. For the most part, that's because they didn't have an OS to test on when OCS 2007 R2 was released, probably not because of known incompatibilities. If there's any more detail in the event log, it might be useful to post that here. Even just having the full first line of the stack trace (Microsoft.Rtc.MRAS.Core..ctor should expand to something bigger; Microsoft.Rtc.MRAS.Core is a namespace, not a type) would help.

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That basically is it. Add to hat that R2 is 64 bit only... and you get into the issue. – TomTom Mar 9 '10 at 8:03

Have you tried enabling the Desktop Experience Feature on the R2 machine?

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Not yet, but I will. But why should this feature be enabled? What has it to do with OCS? – Marcus Aug 28 '09 at 7:26
OCS requires the Windows Media runtime for some of the audio processing it does. In WS 2008 R2 that is installed as part of the Desktop Experience. Counter-inquitive, but it should work. – Jon Rauschenberger Aug 29 '09 at 21:44

I got OCS 2007 R2 working perfectly on a windows 2008 R2 Server, But only deference is it's a fresh installation and not a migration. Even on a fresh installation, "coscore.msi" has to be edited and remove a "launchConditionalValue" ( For screen shots

A work around cab be suggested, where u install a fresh copy of win2k8r2 and ocs r2 on a temporary server, and move the use to that, and remove and reinstall OCS R2 on the upgraded server( the server which u currently having the issue) and move the user back to it.


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