Developer w/ Uninstall/Reinstall Issue

I have a software application that I developed that installs just fine
on Vista machines.

However, for end users to upgrade, it has to be uninstalled before the
new upgrade can be installed. (Yea, I know...)

This works fine in XP, but in Vista the old software version re-appears
after the new installation is complete!

My program's name and install folder (location: c:\program files\...)
needs to be the same due to some internal coding at play.

I'm using a Vista compatable installer package and am including an
uninstall.

Changing the Product and/or Upgrade Identifier does not resolve the
issue.

What can I do or advise my users to do?


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AlphaSnail