ESB Portal Error Could not load type 'System.ServiceModel.Activation.HttpModule' ...

Fixing the “Could not load type 'System.ServiceModel.Activation.HttpModule' from assembly 'System.ServiceModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'’ error for a new installation of the ESB portal on BizTalk 2013:

Open IIS Manager

Open the ‘Default Website’ node
Click on the ESB.Portal application
Go the right hand pane and click on ‘Browse *:80 (http)’

If you get an error page with the message “Could not load type 'System.ServiceModel.Activation.HttpModule' from assembly 'System.ServiceModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'’ then use the following steps to fix it.

1. Click on the IIS root node
2. Click on ‘Modules’ in the middle pane
3. In the middle pane, under the ‘Name’ column, find the ‘ServiceModel’ entry (not the ‘ServiceModel-4.0’ entry)
4. Click on ‘Remove’ in the right pane to remove it
5. Click on the ‘Default Website’ node
6. In the middle pane, double-click on ‘Handler Mappings’
7. Remove current the Managed Handler for svc-integrated (might be called svc-integrated 2.0)
8. In the right pane, click on ‘Add Managed Handler’
9. Enter the following parameters:

• Request Path: *.svc
• Type: System.ServiceModel.Activation.ServiceHttpHandlerFactory, System.ServiceModel.Activation, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35
• Name: svc-integrated-4.0

Click on ‘OK’

Try to browse the ESB Portal again. It should be fine now.