Considerations for Rebuilding the Master Database
When damaged, the master database must be rebuilt if either of the following is true:
A current backup of master is not available.
A backup of master exists, but it cannot be restored because the instance of SQL Server cannot start.
|If you are using the full recovery model for msdb, which is recommended, try taking a tail-log backup of msdb before you rebuild. For more information, see Tail-Log Backups.|
The Rebuildm.exe program was discontinued in SQL Server 2005. For more information, see How to: Install SQL Server 2008 from the Command Prompt.
|Rebuilding the master database installs all system databases to their initial location. If you have moved one or more system databases to a different location, you must move the databases again. For more information, see Moving System Databases.|