Error encountered when running program on PC

Hi Experts,
I have developed a program using VB6. I compiled and ran it on a PC and the program worked fine. I then ran the same program on another PC (a laptop) when this error message popped up (below). I have registered the dlls already but got the same problem. I have searched the web but got no answers.
This site might give me the answers, please help. Thanks in advance.

Messenger API
Run-time error ‘429’:
ActiveX component can’t create object
