Major Upgrade then uninstall leaves all files behind
I built a MAJOR upgrade in IS 2010 Basic MSI which upgrades a 2009 Basic MSI. Major upgrade item added. I install the new version it DOES remove the old version, so that's good, new version verifies as installed and functioning. Now I uninstall the new version that was installed as a MAJOR upgrade and nothing is physically removed. The Add/Remove programs area is clear so it looks like it uninstalled, however, the desktop icon and the program files/myapp folder remains with all contents.
