- You have a computer that is running Microsoft Exchange Server 2010 in a mixed Exchange Server 2010 Service Pack 1 (SP1) and Exchange Server 2007 environment.
- You have another computer that is running Exchange Server 2007 in this environment. This server has Windows Server 2003 and IIS 6.0 installed.
- You configure external Client Access namespaces on the Exchange Server 2010 server.
Note This issue also occurs when you run the Get-ActivesyncVirtualDirectory cmdlet without specifying the Windows Server 2003-based Exchange Server 2007 server.