Unable to launch the IIS Express Web server

I have an asp.net MVC 4 solution. When I try to open it using Visual studio 2012, I get following error:

Microsoft Visual Studio

Configuring Web https://localhost: for ASP.NET 4.5 failed. You must
manually configure this site for ASP.NET 4.5 in order for the site to
run correctly. Could not find the server https://localhost:44300/ on
the local machine. Make sure the local IIS server has been configured
to support secure communications.

OK Help

Although the solution opens. Also, When I try to run it from debug menu, I get following error:

 Unable to launch the IIS Express Web server.

The start URL specified is not valid. https://localhost:44300/

and I can not debug the code. how to get rid of these errors and debug/run the web site from VS 2012 ?

Please suggest.


54 Answers
54

I had the exact same problem.
The reason – bad IIS config file.

Try deleting the automatically-created IISExpress folder, which is usually located at %userprofile%/Documents, e.g. C:\Users\[you]\Documents\IISExpress.

Don’t worry, VS should create it again – correctly, this time – once you run your solution again.


EDIT: Command line for deleting the folder:

rmdir /s /q "%userprofile%\Documents\IISExpress"

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