A. Usual reason for this is that the command only works on SQL 7 mode databases. If you have migrated an existing 6.5 database then it is probably still set to 6.5 compatibility mode. Use sp_dbcmptlevel to check and set it to SQL 7 mode.
Join John Savill for 12 hours of comprehensive Hyper-V training. This master-level online training course will explore all the key aspects of a Hyper-V based virtualization environment covering both current capabilities in Windows Server 2012 R2 and looking at the future with Windows Server vNext.