During an implementation of Lync 2010 I had an issue with the integration of Lync in OWA. This worked on all CAS servers except one. This despite all the needed software prerequisits had been installed:

And the configuration on both the CAS and Front End Server was completed.

After removing the software and reinstalling it again the issue wasn’t solved either. In the application log the following warning was displayed:

An exception was thrown while attempting to load the IM provider .dll file.

File: C:\Program Files\Microsoft\Exchange Server\V14\ClientAccess\OWA\bin\Microsoft.Rtc.UCWeb.dll

Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.

For some reason the dll couldn’t be loaded correctly. The solution was pretty wasu just reset IIS using  IISReset /noforce__.

After running the command the IM integration worked without any issues.


Johan Veldhuis