Essayez également ces méthodes...
CREATE DATABASE AdventureWorks2012
ON (FILENAME = N'C:\ProgramData\Homefront\Database\DB1.mdf')
FOR ATTACH_REBUILD_LOG
GO
OU Essayez ceci...
CREATE DATABASE AdventureWorks2012
ON ON (FILENAME = N'C:\ProgramData\Homefront\Database\DB1.mdf')
FOR ATTACH
GO