I have a copy of Microsoft SQL Server Desktop Engine (MSDE) installed on a Windows 2000 Professional PC. By default, MSDE is configured to use Windows authentication. The database developer didn't provide an MSDE management utility to let us change the security mode. Can we change the authentication mode to SQL Server authentication?

You can easily change the security mode to SQL Server authentication by tweaking the registry. As you do when you make any registry change, be sure you have good backups and use caution because a registry mistake can cripple your system.

Your Windows registry should have a subkey similar to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\SQL2000_1\MSSQLServer\LoginMode. This subkey name is from my machine. Your subkey name will depend on what instances of MSDE and SQL Server you have installed.

A value of 2 for this subkey will set login security mode to support both SQL Server and Windows authentication. A value of 1 will configure SQL Server to support only Windows authentication. You must restart SQL Server to put this change into effect.