The setup during installation only predefines what you *can* use. If you chosse mixed authentication, like you stated above, this should be no problem, you can use WIndows authentication which would be
(...)Integrated Authentication=true(...)
or SQL Server Authentication
(...)UserId=SomeUser;Password=SomePassword(...)
For more information about connectionstrings goto www.connectionstrings.com
HTH, Jens Suessmeyer.
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