If you are installing HMC 4.5 and have reached the point of provisioning where you need to add the server name to the Exchange 2007 default OAB CAS pool, you need to provision the AddOABCAS.xml file.

However as the documentation says, you might receive an error even if you have followed the prior steps correctly:

Note: 
If you run into an error message indicating that EXCASOAB01 is not configured with a distribution point, use the Exchange Management Console to change the internal URL of the OAB distribution to a non-existing URL (for example, http://excas01.fabrikam.com/OAB), and make a copy of the original URL. Then, repeat the above procedure to add EXCASOAB01 into the default OAB CAS pool. After the addition is complete, change the internal URL of the OAB distribution back to the original.

There is a simple way of doing this from the Exchange Management Shell (aka PowerShell). Simply type the lines below to save the current URL and change it:

$oldUrl = Get-OABVirtualDirectory
echo $oldUrl.InternalUrl
Get-OabVirtualDirectory | Set-OabVirtualDirectory -InternalUrl <NEW URL HERE>

Go back to the Command Shell and run the provtest command to provision the AddOABCAS.xml file again. This time it should work. Now simply set the old URL back again in the Management Shell like this

Get-OabVirtualDirectory | Set-OabVirtualDirectory 
     -InternalUrl $oldUrl.InternalUrl

Hope this helps

Tags: hmc, oab, addoabcas.xml, mps
Categories: Internet | Microsoft | Tips