Entity Framework giving exception : “The underlying provider failed on Open.”

Question

I have a test. What happens is that whenever test1 is executed first, test2 fails with the message:

"System.Data.EntityException : System.Data.EntityException : the underlying provider failed on open. cannot open database "DBEntities" requested by the login. The login failed.".

and whenever test2 is executed first, test1 fails with the same message.

I've been at this for the past 3 days.

[TestClass]
class MyTestClass 
{

    DBEntities db;

    [TestInitialize]
    public void Initializer()
    {
       db = new DBEntities(); 
    }

    [TestMethod]
    public void test1()
    {
       db.Books.Add(new Book{ ...});
       db.SaveChanges();

    }

    [TestMethod]
    public void test2()
    {
       db.Books.Add(new Book{ ...});
       db.SaveChanges();
    }


    [TestCleanup]
    public void Clean()
    {
       db.Dispose(); 
    }

}

Here's an excerpt of the DBEntities class :

public class DBEntities : DbContext
{
    public DbSet<Books> TheBooks{get;set;}
    ...
}

After running a profiler, I noticed this message:

"Login failed for user. Reason: failed to open the explicitly specified database."

after a lot of lockAcquired and lockReleased statements.

Answer 1

Might the issue be connection pooling? Would the SQL provider try to preserve the connection between tests, even though the EF object is disposed? In that case would it be having an issue w/ multiple connections to the same DB by the same user?

Try explicitly closing the connection in your cleanup:

db.Database.Connection.Close();

Answer 2

The important part of the message is:

Login failed for user 'domain1\\user1'..

If the DB rejects the login info you pass, then the EF can't work.

Answer 3

Sometimes, you can type "iisreset" in the run box it will clear up the issue you described, especially if everything was working fine and all of the sudden it stopped working. This error can happen due to lack of memory on your system. (In my case at least)

Answer 4

如果通过IIS运行，请检查附加到Web应用程序的IIS池的身份