>The others have given you the how. FWIW I've just taken to using MSK files that are solid black, there really isn't a need paint only white areas.

David,

This is not quite true..

Try changing your colour scheme, you will end up with your buttons staying the same colour (grey) and the rest of the application background a different colour.

It's not that hard to make a proper .msk, just open the bmp, convert it to monochrome (In MS paint, Image attributes, Black and white) then flood fill the inside of the icon with black.. then save as .MSK