To start a named instance of SQL Server from a command prompt
sqlservr.exe -c -s {instancename}
Note You must switch to the appropriate directory (for the instance of Microsoft® SQL Server™ 2000 you want to start) in the command window before starting sqlservr.exe. For example, if Instance1 uses \mssql$Instance1 to store its binaries, you must be in the \mssql$Instance1\binn directory to start sqlservr.exe.