Shell programming problem, about context menu

[scchan1984]

hi all, I have followed the tutorial in this site about how to add items in the context menu. But I don't know why I integrate it with another sample code, which is about cascading menu, the explorer.exe halt. The problem happens when I rightclick on some empty spaces (not on files / folders) or the desktop. Am I missing some controls to the context menu for that, besides files / folder? What should I do? Thank you very much