Hi Gordon,

Unfortunately, this is not possible currently in SQL Server. SQL Server (for some reason) cannot read members out of the AD group configured as a login in SQL Server itself (both AD and SQL Server are Microsoft products, right :crazy: ?).

The impersonation is possible only when the impersonated login exists in sys.server_principals.

Check the similar topic at http://www.sqlservercentral.com/Forums/Topic1434100-1526-2.aspx.