It is an error to use a section registered as allowDefinition='MachineToApplication' beyond application level This error can be caused by a virtual directory not being configured as an application in IIS.
Got the following error some time back when i tried running the project,
since it said that it wasn't configured to be debugged i ran it with the good old "CTRL + F5" option and got the following error message in IE:
My first guess after reading the error (make that reading half the error) was that somehow there was some configuration problem regarding who overrides whom in the web.config and the machine.config.
but after reading the Total error message understood that the error wasnt in the Web.config it was in the IIS virtual Directory settings that I had ,somehow it had changed.
Anyways, here is how to solve the error :-
Just open IIS and goto the properties for the Virtual directory and click on this button