Login Failed for user Domain\MachineName$ on IIS 7.5 with an ApplicationPoolIdentity

Actually I was expecting a SqlExcpetion like Login Failed for user IIS AppPool\My AppPool Name exception instead of Domain\MachineName$.

I've created an Application Pool that is using

• Manged Pipeline Mode : Integrated
• Identity : ApplicationPoolIdentity

This AppPool is assigned to the We开发者_如何学JAVAb Application (MVC3) in question. But somehow it seems that the WebApp is using somehow the NetworkService for the connection to SqlServer.

Any Idea why or what I should change?

Turns out that I forgot to change the connection string to SqlServer.

So they where pointing to another machine in the Network, as IIS AppPool\My AppPool Name is only valid on the local Server, IIS takes automatically the Network Service to access stuff in the Network, that's why it was showing Domain\MachineName$.