The environment: Three 2007SP2 servers (one is CAS, one is MBX, and one is SCR at remote site. I just added my first 2010 CAS server and am just starting to configure. I'm getting this error in the 2010 manager - "An IIS directory entry couldn't be created. The error message is The remote procedure call failed and did not execute. HResult = -2147023169 It was running the command 'Get-OwaVirtualDirectory' " I added the group Exchange Trusted Subsystem to the local admin group of the three 2007 servers. That fixed a number of errors. --Patrick

I figured it out. I had to click on the 'Configure External Client Access Domain...' link at the top right. I added a second 2010 CAS server and had to do it again after that one. --Patrick