We recently moved an ASP.NET MVC website to a new provider and found out that the MVC application is no longer connecting to SQL Server database. That was surprising because it was up and running with previous provider without any issues.
Below is the exception I got while connecting to SQL Server:
Login failed for user 'IFC\WIN5177$'.
That took quite sometime to figure out what was the issue. And, I finally fixed by setting Integrated Security=False; in the connection string,
Hope this helps.