Screen sporadically blank / clear color

This is strange…

I’ve been working on this one OpenGL program in C++ for about a month now (in win98). Every so often after I change something, something weird happens:
I’ll run my executable and it will just be a blank screen full of whatever the clear color is. Then I’ll x out of it, and run it again right away, and everything is then fine.

Twice, though, it wouldn’t fix itself after re-running it, and I would reboot the computer and it would then be fine.

Could this have anything to do with incorrect memory management or something?
Any ideas at all?
Thanks

-Ray