When you get the following error message in Microsoft Visual Studio 2013 check the inner exception.
System.Data.Entity.Core.EntityException was unhandled
HResult=-2146233087
Message=The underlying provider failed on Open.
Source=EntityFramework
The inner exception gives you detailed information on the real cause of the error. Most of the time the inner exception is the following:
InnerException: System.Data.SqlClient.SqlException
HResult=-2146232060
Message=Cannot open database “…” requested by the login. The login failed.
Login failed for user ‘…’.
Source=.Net SqlClient Data Provider
ErrorCode=-2146232060
Check the rights of the user. Most likely the specified user does not have access to the database.
Thanks for this – actually found it quite useful, though my inner issue was different.