Custom DNN module won't be dropped onto a page

Question

I have a custom DNN module that works well in DNN 5. After modifying the module to work in DNN 7 and installing it successfully, nothing happens when I drop one of the module's controls on a page. In the event viewer, I see the following log entry of type 'Host Alert':

=============================================================================

EventQueue.ProcessMessage: Message Processing Failed

ProcessorType: DotNetNuke.Entities.Modules.EventMessageProcessor, DotNetNuke

Body:

Sender:

BusinessControllerClass: Nedoweb.Modules.Survey.SurveyController

desktopModuleID: 87

ExceptionMessage: Value cannot be null. Parameter name: type

Server Name: MyComputerName

=============================================================================

Any help is greatly appreciated!

Answer 1

I would start by looking at your SurveyController class, what classes are you inheriting from? What interfaces are you implementing there? IPortable? Anything else?

You might try fixing that class, maybe even comment out all the interfaces, and then try the install to see what happens with the module.

Answer 2

If you have access to the module source, the easiest way to trace that bug would be to install DotNetNuke 7 locally and running a debug with a breakpoint in each method of your controller class in visual studio. Then you can run your code line by line using F11 and see exactly what is happening behind the scene.