Scenario: If you have two controllers with the same name in different areas, then you would end up with errors as shown below, while there are numerous examples available on the web but it took me a while to figure out the correct solution for VB.
Hope it help you and saves you time.
Problem Description
I have a HOME controller in my MVC4 application and then I created a new AREA called SUPERADMIN. I then created a HOME controller in that area as well.I received the following error.
Solution:
1. Fix the Route.Config in your MVC4 project under APP_Start folder. See the yellow coloured text,
vbnull is for constraints( so we are not adding special constraints
the next one “RealEstateVB” is the namespace , RealEstateVB is the name of my application and is taken as the default namespace.
2. Now Go to your AREA. I had an area called SUPERADMIN.
See the highlighted text. You have to define the namespace. eg. I have used “RealEstateVB.Areas.Superadmin for my SuperAdmin area.
Also make a note how I have added superadmin in front of the /{controller}/{action}/{id}
This should get your project going without any errors. For each area you have you will need to fix the xxxAreaRegistration.vb file as described in the above step(2)