"Dmitry Timoshkov" dmitry@baikal.ru writes:
The problem with Rob's patch is that it causes entire background of the progress bar to be repainted. Some time ago (3 years or like that) I wrote tests for progress bar and found that it invalidates background only when (oldPos < newPos) and it really has a separate WM_ERASEBKGND handler. Since then my code has been removed and rewritten (by you Alexandre) for no obvious reason IMO.
The reason was precisely to avoid flicker in certain cases (I believe it was during the MS Office install).