double clicking a file should open it

[retry]

I am trying to open the file in my application when you double click the file (or likewise from the context menu). Assume a file type of extension .abc which is unique to the pc.

I ran this through Jeff Prosis (Programming Windows with MFC) that the following lines should do all the work after AddDocTemplate(pDocTemplate); line in InitInstance()

AddDocTemplate(pDocTemplate);

CWinApp::RegisterShellFileTypes(TRUE);
CWinApp::EnableShellOpen(); 

However this doesn't register the file types and the context menu are the same as before and double click doesn't work. Is there anything else need to be done?

Thanks