DPI Setting Makes Program Inoperable

Setting the DPI scaling to other than 96 makes our program inoperable. This
is because Vista tells us that the screen resolution is 96 DPI when it is
not. We use this value in screen hit testing and so clicking on things on
screen does not work. It works correctly if we check the "Use Windows XP
style scaling" checkbox.

Our program is DPI aware. I know about the SetProcessDPIAware call which can
fix this problem going forward but it does not fix it for all currently
existing of the copies of our program. I also know about the compatibility
setting that the user controls. There are plenty of workarounds. I just
wanted to make the point that the behavior of the Vista RC1 beta breaks our
program which is DPI-aware.