I did port some of my development environments to a new virtual machine with a brand new 2008 R2 Server and a Visual Studio 2012. Everything seemed fine until I tried to load one of my Umbraco labs. The error Handler "PageHandlerFactory-Integrated" has a bad module "ManagedPipelineHandler" in its module list showed up.
This is quite simple to resolve for Umbraco
- ensure your application pool runs in .net 4 classic mode in IIS
- run the aspnet_regiis.exe -i command, to run the aspnet_regiis command
- navigate to C:\Windows\Microsoft.NET\Framework\v4.0.30319 (or whatever .net 4 framework version you have)
- type aspnet_regiis.exe -i and press enter