Yes I am. I also downloaded Windows Installer clean up at someone's suggestion. I also tried installing 3.5.2 to several different directories, and no luck. Very frustrated. Seems like this is a common bug the Paint.net folks should fix.
I tried to install also. Got 1603 fatal error unable to install. Checked add/remove programs for old version, couldn't find it. downloaded windows installer, and paint wasn't listed.