Can't change authentication

[kevinkwh]

hi I'v used Windows xp and used VS 2010 with Sql express .
It was fine when I used those.
Recently I decided to use Windows 7 and installed the above softwares.
After installing those softwares, When i tried to change the SQL authentication Mode , it shows
"EXECUTE permission denied on object 'xp_instance_re gwrite', database 'mssqlsystemres ource',schema 'sys'.(Microsof t SQL Server,Error,22 9).
I don't know what is wrong.
What should I do?
I wanna use SQL Server and Windows Mode for authentication.
Thanks in advance.

[MrMancunian]

Try enabling the SA-login on your SQL server. Right-click your server, select New Query and enter:

Alter login sa enable

That should do the trick :-)

Steven