Wise Program Uninstaller is a free application which can fully uninstall other software, without leaving any disk debris or orphaned Registry keys.
Although it's aimed at helping you reduce the number of programs on your system, for some reason it requires installation itself, and - even worse - by default will install other applications unless you notice this, and hit Decline.
Get past that and the program is more like any other uninstaller. Here's a list of installed programs, scroll to or search for the one you need, and launch a regular or forced uninstall.
The results dialog listed our main application folder, the Start Menu entry and desktop shortcut. It also found our HKLM\Software and HKCU\Software Registry keys, and the file association.
Missed items included our service, the associated Users\Name\AppData\Roaming folder, and, crucially, some of the installer Registry keys (when we ran our test setup later it thought it was still installed).
What's new in 2.31.132 (Changelog):
Improved the uninstallation of long-name programs.
Minor GUI improvements.
Updated various translations.
Minor bug fixes.