I've had an exception occur on a couple of different, unrelated projects which have come from either book code or Web tutorial code. It is around the Entity Framework and says:
Entity Exception
The underlying provider failed on Open.
I 1st thought there might be something wrong with my PC, but I get the same errors with those projects on my laptop.
I changed the DataConnectionString to point at my local database in those projects.
I did up a quick fresh project with an Entity Data model and it worked fine.
So I am at a loss as to why these projects are failing.
Any clue?