Here is the situation... Be warned that it is a really weird bug...

I have a "home made" class that contain a grid, with check box on the first header of the grid. Last Friday, I update a client's version of my program which use that class. The client run on a server with several workstation. On all the workstation, it works fine, but on one of them, the first header with the check box in my class is not there anymore. I checked here and it works fine, and it work fine also in the other workstations I updated. I also check some other form that use checkboxex but not in that class and they were there.. This is the very first time I see this, and I really have no single clue of what that could be. I kinda suspect the run-time may be in fault here, but I really can't say for sure.
If there is a way I can possibly post my class to show what it looks like, just tell me and I'll do it.

any idea of what the problem could be??? Any solution to it?