The underlying provider failed on open entity framework

"The underlying supplier failed on Open," says Entity Framework.

You should create a sql account for your web server to access the aspnetdb database. It is currently using integrated authentication (tries to logon with the identity the web server is using to run the application)....The example below uses integrated auth. I would use SQL auth though....http://msdn.microsoft.com/en-us/library/ff649314.aspx

"The underlying supplier failed on Open," says the Entity Framework error.

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();

"The underlying provider failed on Open" with WCF, Entity Framework, and SQL Server

Well I had the same error for days... actualy for two days and Yes ...I found the solution... Alhamdulillah.....As for me... I had Windows Authentication set on my Entity Service Connection.. So What I did was I went to IIS 7 Application Pool Advanced Settings for the web service... Changed the Identity from 'ApplicationPoolIdentity' to 'Network Se...

The underlying provider failed to open , login failed for user IIS APPPOOL

If all of your Web.config files are correct, SQLSERVER has the appropriate permissions, etc., there's one more thing you can check. I once had this issue when a client had me configure the project so that Entity Framework would not automatically drop the databases (if, for example, the models changed), but I was still testing the project on localho...

The underlying provider failed on Open in entity framework connection

I don't know why you get this error but I use this connection string and I don't have any problem. remember the name of the DbContext class and connection string should be same...<add name="MyDB" connectionString="Server=127.0.0.1;User ID=sa;Password=password;Database=Database" providerName="System.Data.SqlClient"/>

Entity Framework The underlying provider failed on Open

Search "Component Services" in Programs and Files...Go to Services...Find "Distributed Transaction Coordinator" Service...Right click and Restart the Service...You've just done a restart of the service and the code should run without errors

Entity Framework Exception "The underlying provider failed on Open"

In my case, the issue was that the account which I was using to connect to SQL server was not added to app pool identity. Once I added the account 'domain\username' to app pool, it started working.

Entity Framework: The underlying provider failed on Open - through WCF service

Probably the app pool user you have the WCF service running against does not have permissions to access the sql database. You can either add yourself as a user or assign permissions for the current app pool user....Similar problem to ...How to use domain windows user account as app pool identity

Using singleton pattern with Entity Framework context - The underlying provider failed on open

May I suggest you to use "lock" functionality to access your singleton object :...public sealed class XModelInstance { private static XDBEntities edmx = null; private static readonly object padlock = new object(); private XModelInstance() { } public static XDBEntities Edmx { get { lock (padlock) ...

SQLite & Entity Framework 6 "The underlying data provider failed to open"

You cannot use a SqlConnectionStringBuilder with SQLite, use SQLiteConnectionStringBuilder instead, and set the DataSource property to the database file name