This post shows you how to fix the following IIS error message: Handler "PageHandlerFactory-Integrated" has a bad module "ManagedPipelineHandler" in its module list This error occurs when the IIS module is incorrectly registered (nope, I don't know what that means either.) But to fix it, follow the steps below:

• First open explorer by holding the windows key and pressing E
• Then open the drive that Windows is installed on (Most likely C:)
• Navigate to "C:\Windows\Microsoft.NET\"
• If you have a 64 bit computer, open the folder "Framework64", otherwise "Framework32"
• Now open the folder named with the highest version of ASP.NET you have installed (most likely something like "v4.0.30319")

Now you have found this folder, you need to navigate to it in command prompt with administrator permissions:

• Click "Start"
• Type "cmd"
• Right click it and click "Run as administrator" then accept the user account control popup
• In command prompt, navigate to the folder we navigated to earlier. Do this by typing "cd" followed by a space, and the path
  • e.g. "cd windows\Microsoft.net\..." etc
• Now when in the correct folder, type "aspnet_regiis.exe -i"

You should see a success message and IIS will work.