Can't view Quicktime files on XP (H:drive problem?)

[Richard Miller]

I'm lost on this one and need some guidance.

I have a customer who is using Windows XP. My software installs files  
to a folder inside My Documents on the C: drive. When the software is  
running, it allows the user to view Quicktime videos stored in this  
folder.

This user, however, cannot view those videos. The software sees the  
video files.. it knows they are there. But when the user attempts to  
view them, nothing happens. He says he just sees white. There are no  
bugs in my software... hundreds of people use it regularly with no  
problem. But this user has a drive configuration I'm not familiar  
with, and somehow it is creating this problem.

His system continually (and automatically) backs up everything in the  
C: drive "My Documents" folder to his company's networked server  
(which shows up on his computer as an H: drive). Somehow, this is  
preventing these Quicktime files from being viewed from within Rev.  
He can manually open one of these files directly in Quicktime with no  
problem... but they can't be viewed in my Rev program.

Any idea what's happening here?

Thanks.
Richard Miller