ChoosePixelFormat Access Violation

I use ChoosePixelFormat while initializing a render context. I debug it using BCB 3.0 and sometimes I get Access Violation. But when I run my app without debugging it seems to work properly. Does anybody know waht's the reason for that and how to overcome it?

Rozz

[rIO]

Card vendor ? Drivers version ? OS ?
Give some more info...


rIO.sK http://www.spinningkids.org/rio

I work on Matrox G450 but the same exception is thrown on GeForce 2 MX. It's under MS Widnows.