Possible Duplicate:
How to recover a MSSQL user's password?
We recently installed SQL 2012 on one of our servers, but have been unable to log in. Another tech did the installation so I don't have the details, but I suspect that he did not configure a login account, either SQL or Windows Authentication. How can I get in to my own SQL server without knowing a valid login?
Edit: Before anyone asks, it definitely appears to be an authentication issue. The exact message from SQL Server Management Studio is "Login failed for user ''. (Microsoft SQL Server, Error: 18456". Also, the SQL service account has been set to use the user account that I am trying to log in as, which I would have thought would be enough to let me in
