Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

I've been trying all sorts of different combinations of startup flags to SQL Server 2008 R2 Express and I can not get past this error:

Login failed for user 'LOCALSERVER\Administrator'. Reason: Server is in single user mode. Only one administrator can connect at this time. (Microsoft SQL Server, Error: 18461)

I've tried starting it up in Single User mode by both -m"SQLCMD" and -m"sqlcmd" and Iv'e even tried to start it up with -m"Microsoft SQL Server Management Studio - Query" and connecting with the appropriate clients I ALWAYS get this error. I'm 99% sure that nothing else is stealing my connection and when connecting with SSMS I make sure to do the "new query-connect` method to ensure it only uses 1 connection.

Has anyone else had this problem? How do I fix it and login?

share|improve this question
add comment

2 Answers

Despite Microsoft saying otherwise you shouldn't quote after the -m. So for SQLCMD, you'd do -mSQLCMD. I didn't see this said anywhere, so I'll document it here. If nothing else works, try not quoting it.

share|improve this answer
add comment

There should't be anything after -m. The syntax should look like:

sqlservr.exe -c -f -m 

You then log into the instance using sqlcmd and make the needed changes. If you try to use SQL Server Management Studio to log in you won't be able to as SSMS requires several connections to log in.

share|improve this answer
-m can be optionally suffixed by a "client name", in my case I needed it to be sqlcmd because other things would be trying to connect and steal my connection. –  Earlz Dec 6 '11 at 20:55
add comment

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.