Issue:

Just now I got the below issue when i try to browse the new web site deployed in IIS.

HTTP Error 500.21 - Internal Server Error

Handler "WebServiceHandlerFactory-Integrated" has a bad module "ManagedPipelineHandler" in its module list.

Solution:

To fix this, Simply I ran the following command at the command prompt with Admin rights

If I had been on a 64 bit system, it would have looked like the following:

%windir%\Microsoft.NET\Framework64\v4.0.30319\aspnet_regiis.exe -i

If I had been on a 32 bit system, it would have looked like the following:

%windir%\Microsoft.NET\Framework\v4.0.21006\aspnet_regiis.exe -i

Reference

http://stackoverflow.com/questions/6846544/how-to-fix-handler-pagehandlerfactory-integrated-has-a-bad-module-managedpip