SCOM 2012: Webconsole fails to load after upgrade
In my recent session I’ve showcased an error I encountered when upgrading my SCOM2007R2 environment to SCOM2012beta.
After the upgrade was finished successful I performed my standard after migration health check and opened my web console to check out the new features of the SCOM 2012 console.
Only to find out this very “nice” cryptic error message:
Apparently this is because the ASP.NET version was installed after the IIS role and the new web app “SCOM 2012 Web Console” was never registered to use this version of ASP.NET with the IIS role.
So what are we going to do now… well euhm… Fix it 
Open an elevated command prompt (make it a habit, this will save you a lot of trouble in your live)
Open explorer and browse to “c:\windows\Microsoft.net\Framework64\v4.0.30319\”
Note: Make sure you use your installed framwork and version
Locate the file aspnet_regiis.exe and drag it into your elevated command prompt and add the switch –iru at the end as shown below. 
This actually will reinstall the ASP.NET version into the IIS sites so they can all use the new version. Sites which already use the new version are left untouched.
Finished installing… So we’ll see what happened to our console!
Well it’s loading up fine at this point
Note: You’ll need to have Silverlight installed. If you don’t have it on your machine a nice kind message will appear whether you want to install it. I’ve installed it in advance as it is one of the prerequisites.
There we have our nice brand new shiny Scom 2012 web console which we can start exploring