Error when trying to access ConfigMgr 2012 Self Service Application Catalog

After installing the Application Catalog Web Service and Web Site the other day I was presented with this error when trying to access it:

"Could not load type 'System.ServiceModel.Activation.HttpModule' from assembly 'System.ServiceModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'"

I thought this was a little strange as this is usually related to when IIS is installed after .Net Framework 4, which I had definitely not done as this was the same server that I had previously had the ConfigMgr Beta 2 installed on, with a working Self Service Portal before uninstalling ConfigMgr Beta2 and re-installing the Release Candidate.

But I thought I had best try the simple fix first, which involves just simply running the aspnet_regiis.exe -iru command.

And would you believe it, it fixed it!

So if you do run into this error, even if you're pretty sure you installed IIS & .Net Framework in the right order, give this simple fix a quick try first.