There is a problem with your selected data store. This can be caused by an invalid server name or credentials, or by insufficient permission. It can also be caused by the role manager feature not being enabled. Click the button below to be redirected to a page where you can choose a new data store.
The following message may help in diagnosing the problem: Specified cast is not valid.
I'm not sure how it happened but after changing a column in my AccommodationComment table from memberId to username I tested it and all pages which have to do with selecting current user or any user says:
System.InvalidCastException was unhandled by user code
Message=Specified cast is not valid.
at System.Data.SqlClient.SqlDataReader.GetGuid(Int32 i)
at System.Web.Security.SqlMembershipProvider.GetUser(String username, Boolean userIsOnline)
at System.Web.Security.Membership.GetUser(String username, Boolean userIsOnline)
View Complete Post