Program works fine on my machine, fails on all others

Hi.
I have a program that I have been writing for several months. Whenever I
have tested it on another machine, it has worked fine. However, the last
time I copied it to my test machine, it didn't work. The splash screen came
up, and right before the main form of my program displayed, it came up with

'Module HTMLPro.exe cause an exception eedfadeH in HTMLPro.exe at
[address]'.

I tried it on several other machines and it didn't work there either. I
don't know what to do to debug it if it runs fine on my machine, but doesn't
on any other machine. Any ideas?

Thanks
Joel Broughton