Unable to launch the IIS Express Web server

Question

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.

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Answer 1

It seems you need to do some configuring as you seem to be using SSL; here's a step-by-step guide by Scott Hanselman himself:

http://www.hanselman.com/blog/WorkingWithSSLAtDevelopmentTimeIsEasierWithIISExpress.aspx

Answer 2

I'd set up Internet Connection Sharing on my machine for virtual machines. I switched it off and I was able to debug in Visual Studio 2015. However to consistently debug following a reboot, I needed to set the Internet Connection Sharing service to manual start up, even though none of my internet connections had Internet Connection Sharing enabled.

Answer 3

Sharing this for future readers. Manually creating a virtual directory worked for me.

• Select project in solution explorer
• Press Alt + Enter
• Go to Web section
• Click Create Virtual Directory

Answer 4

Same Problem, but needed to start VS2013 in Admin Mode.

Answer 5

I had the same issue, the cause was that the flag "override application root URL" was set under Properties --> Web After I removed the flag, IIS Express was starting fine with the defined port.

Answer 6

check the antivirus firewall and allow access visual studio to network. for example in nod32:

goto setting (f5) -> network->personal firewall->rules and zones

in the "zone and rule editor" click "setup" and find the vs 2010 or 12 or ... and allow access to network.