I am getting multiple errors when I try to open an existing or creating a new project.

When I try to open an existing project this is the error:

"Unable to get the project file from the Web server. Unable to open Web project 'WebApp1'. The file path 'some path' does not correspond to the URL 'some URL'. The two need to map to the same server location. HTTP Error 401: Access Denied"

When I try to start a new project this is the error:

"The Web server reported the following error when attempting to create or open the Web project located at the following URL: 'http://localhost/WebApplication1'. 'The server returned an invalid or unrecognized response'."

I have been trying to fix this problem for the last couple of days. I have tried everything including going to devenv.exe.config and checking all of the IIS settings. Please help, thanks