When you uninstall MatchMaker, there may be files created by the program that are left over. It is best to remove these manually, although the program will probably work fine if you skip this step. The exceptions may be occasional conflicts between old and new versions of images.

Delete these folders (if present):
C:\Program Files\MatchMaker\ (just the MatchMaker folder, not the whole Program Files folder) and
C:\MatchMaker_Data\

This is easiest to do using the program Windows Explorer, found under Accessories under All Programs on the Start menu, or the My Computer program (called Computer in some versions) on the Start Menu. One of these programs may already be on your desktop.

If you have Version 1.31 (or before) installed on Windows Vista or Windows 7, uninstalling that version of MatchMaker might leave leftover files in the folder
C:\Users\username\AppData\Local\VirtualStore\Program Files\MatchMaker\
where "username" is replaced by the name on the account you are using.
Use Windows Explorer or My Computer as in the paragraph above.