If I run DBCC CHECKDB I get the following error:

Msg 7928, Level 16, State 1, Line 1

The database snapshot for online checks could not be created. Either the reason is given in a previous error or one of the underlying volumes does not support sparse files or alternate streams. Attempting to get exclusive access to run checks offline.

DBCC results for 'CommercialLinesWDB'.

DBCC CHECKDB will not check SQL Server catalog or Service Broker consistency because a database snapshot could not be created or because WITH TABLOCK was specified.