Unable to create the virtual directory. The URL ... is already mapped to a different folder

I setup my web project to run locally using IIS Express.  It worked for a while, but eventually I started getting the following error:

Unable to create the virtual directory. The URL ... is already mapped to a different folder

I wasn't quite sure what I'd changed to cause this to start happening.  I'd get this error when I was opening my solution.  My web project wouldn't even load.  I had to edit the csproj file manually and change my project to use "localhost".

This would allow my project file to open, but it wouldn't solve the problem.  When I changed it back from LocalHost it would just break again.

SOLUTION:

I found that my IISExpress had been cluttered up by past configurations and projects.  I had to clean up my applicationhost.config file, which is located here:

<UserProfile>\Documents\IISExpress\config

I just searched this file for my project folder path and removed sites that referenced that same path.  Once I did that, I could change my project back to something other than LocalHost and everything worked fine.

dbmdl could not be created, Internal Error: Ese could not be initialized

Lately I've been getting the error "DBMDL file could not be created, it might be locked by another application ... DBMDL file could not be created, it might be locked by another application" when opening database projects in Visual Studio 2013.