Must be something with pixel attributes in true color bitmaps, I think. The result is that bitmaps are no longer transparent. I've fixed the issue by refilling the white again with white :-) in an image editor (ImageForge) with RGB(255,255,255) and Luminance set to 255. This worked.
Another suggestion if you want to use true color bitmaps. For disabled states of buttons, use a copy of bitmap converted to gray and point DisabledPicture property of button to it. Otherwise, buttons will look bad.

Dorin

>I have a problem with a couple of bitmaps that I have put on a form. I created masks on my XP machine which is set to True Color. When these are installed on a Win98 machine using High Color, I get a background image. Changing the Win98 machine to 256 colors fixes the problem, but that's not desirable of course.
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>Is this because there are too many colour planes in the BMP? Any/all suggestions gratefully accepted.
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>Regards
>Simon