Database '%.*s' is not in single user mode ¾ may find spurious allocation problems due to transactions in progress.
This error occurs when you execute dbcc checkalloc on a database that is not in single-user mode. The error will appear and dbcc checkalloc will continue to execute.
If the database is not in single-user mode, dbcc checkalloc may report errors that do not reflect the actual state of your database. These errors are referred to as spurious.
If errors are reported after executing dbcc checkalloc, run dbcc checkalloc in single-user mode. Any errors reported then are real errors. Be sure to reset the single-user option back to false, as shown in the following example:
use master
go
exec sp_dboption pubs, 'single user', true
go
DBCC CHECKALLOC ('pubs')
go
exec sp_dboption pubs, 'single user', false
go
For details on modifying database options, see the sp_dboption system stored procedure in the Microsoft SQL Server Transact-SQL Reference.