Troubleshooting master database corrupted in SQL Server

 One of an instance master database data file was corrupted and I was unable to start the server. How to troubleshoot this scenario?

Possible Scenarios

If the master files are corrupted or damaged, instance cannot be started. We have to rebuild master database then by running the server in single user mode we have to restore latest backup to get previous settings.

Steps

1.      Check the error log for exact reason.

2.      Rebuild master database as follows by running setup from

C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Release

For windows authentication:

setup /ACTION=REBUILDDATABASE /QUIET /INSTANCENAME=<instance
name> /SQLSYSADMINACCOUNTS=<accounts>

 

For mixed mode:

setup /ACTION=REBUILDDATABASE /QUIET /INSTANCENAME=<instance
name> /SQLSYSADMINACCOUNTS=<accounts> /SAPWD=password

3.      Once rebuilding is completed then run the server in single user mode

4.   Restore master database by replacing existing one.

Restart the server in multi user mode.