PrintWindow Occasionally Includes Black Rects

[Xiphias3]

Greetings fellow Vee-B-Six-Erz!

I have a question on the useage of the PrintWindow API call.
When I call this function, i occasionally get black rectangles im places where an obvious child window lies. For example, at times when i call PrintWindow passing a Explorer window the file explorer child window (SysListView32 i believe) comes up as a black rect, other times it OK. I tried calling UpdateWindow() before the call and it still happens. Called LockWindowUpdate because i hear PrintWindow sends "erase window background" message and pretty much everything came up black. Tried Doevents before and after the call and the same thing happens. Tried Sleep(0) before the call (yes someone did suggest it), same thing.

I read alot of posts about it and could never find a difinitive answer.
Im using Windows XP SP2, could it be the OS?

The code im using is straightforward, and working. Just occasional black rects.
Heres an example of the "Black Rect" i occasionally get. Notice the Explorer window on the left:


Thanx for any replies,
-Xiphias3