Uninstalled Parallels Trial but now GOM won't play videos

I played around with the Parallels Trial and when it expired I deleted it by dragging to the Trash and emptying it. Now whenever I try to play a video file I get an error pop-up saying 'The "GOM Player" application cannot be started. The application is installed in a virtual machine that cannot be located. blah blah blah'.

I've finished with Parallels and just want my Mac back to normal. What should I do?