HTTP Error 500.21-internal Server error

The error message is as follows:

HTTP Error 500.21-internal Server error handler "pagehandlerfactory-integrated" has an error module in its module list "Managedpipelinehandler"

Cause of Error:

VS2010 defaults to the. NET 4.0 framework, the 4.0 framework is a standalone CLR, and, unlike. NET 2.0, if you want to run the. NET 4.0 Framework's Web site, you need to register the. NET 4.0 framework with aspnet_regiis and then use the. Net 4.0 framework of the class pool, you can run the Web project of the. NET 4.0 framework.

Solution:

Myself. NET4.0 directory is "C:\Windows\Microsoft.NET\Framework\v4.0.30319"

1. Run cmd

2. Execution: CD C:\Windows\Microsoft.NET\Framework\v4.0.30319

3. Execution: Aspnet_regiis.exe-i wait for installation to complete

HTTP Error 500.21-internal Server error