|Here you go, from the developers: http://www.opencandy.com/faqs/#unin...|
You should probably read that whole page while you're at it.
It would help to know which programs you previously tried and in which way you tried them. Also, report any scan results they provided.
In the future, never rush through a software installation, always use the Advanced install method if it has one, and read everything clearly. If you're unsure about something, ask before installing.
Apologies if I don't respond to your reply immediately. I don't check this site daily, but you're welcome to PM me as a reminder.