IIS express not working in visual studio 2012

asp.net visual-studio-2012 iis-express iis-8
Pa1 picture Pa1 · Mar 23, 2013 · Viewed 20.7k times · Source

Iam not able to run the Visual Studio Application with IIS Express. Iam getting an Error “Unable to launch IIS Express” for the first time. After multiple times debugging, Iam getting the below error, enter image description here

If I run IIs express manually through command prompt,iam getting the below error, enter image description here

I have reinstalled IIS Express but there is no change. I have also modified the application host config file of IIs express by deleting all the site names of application but there is no change.

Iam not able to know the issue. So, plz suggest any solution for fixing this issue.

Answer

Mike Beeler picture Mike Beeler · Mar 26, 2013

I had the same problem and the problem is related to the app pool definition which you can find in \users{your username}\mydocuments\IISexpress\config\applicationhost.config.

Find the tag 

<add name="Clr4IntegratedAppPool" managedRuntimeVersion="v4.0" managedPipelineMode="Integrated" CLRConfigFile="%IIS_USER_HOME%\config\aspnet.config" autoStart="true" />

and change the managedruntimeversion from "v4.0" to "v4.0.30319" for .net 4.5 

<add name="Clr4IntegratedAppPool" managedRuntimeVersion="v4.0.30319" managedPipelineMode="Integrated" CLRConfigFile="%IIS_USER_HOME%\config\aspnet.config" autoStart="true" />

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