>I don't think I have a password 'sa' set in my database. But I need - somehow - to have access to the database right now from .NET method. And I have no password to use. In VFP connection string I don't specify a password and I thought that the same could be applied to .NET world. When I use MSSMS to access my SQL DB I have Windows Authentication.

I also use Windows Authentication for my local tests - I'll give you my connection string in a sec.