Last BETA version of TOAD SS 18.104.22.168 , but the problem was present with old beta version of it.
I use Microsoft Windows 8 pro at 64 bits in italian with last windows update from Microsoft web site.
My machine account is member of Administrators group.
I uninstall TOAD via control panel add/remove programs.
When I uninstall BETA version of TOAD I obtain warning that you can see in attach.
I press OK button and uninstallation continue without problem.