F1 2011 "Another version of this product is already installed" when removed

[WillBarnes1999 0]

Hi all, I recently purchased F1 2011 on disc (GFWL) online and when I came to install it I got a message saying another version was already installed. Sure enough when I went to control panel I found that I had previously installed it some time ago (probably when a friend came round). But when I clicked the button to uninstall I got the same error.

I found out that I had tried to manually uninstall the program in a rush last time I had used it as I had deleted the F1 2011 folder in program files. So I checked in regedit to look for any remaining traces of the game being installed and sure enough I found some matches, which I then deleted.

I then tried to delete F1 2011 with CCleaner, I deleted the install entry having renamed as the main "Uninstall" button was not working and I read I had to do another way. Then when I went onto F1 2011 on control panel under add/remove programs it said that the program had already been uninstalled and deleted the option to uninstall. So I then went to launch F1 2011 and STILL I get this error that the game is installed! 

After several restarts and attempts to install patches so I can uninstall I'm still left with this error whenever I launch the installer, whether that be Game.msi, Autorun.exe or the setup.exe.

Please help! :(

P.S. It's worth mentioning that I am running WINDOWS 8 and I have tried running in compatibility and as an admin!