Your Articulate Presenter project cannot be upgraded... '13 file

Hi,

I initially had '09 on my machine, and then downloaded '13 - during the install it says it's removing older versions of the software, but '09 is still there. (I've done this three times, and rebooted in between each time...)

I can't uninstall '09 from the Control Panel. Now both ribbons are showing in PPT - but '09 doesn't do anything & any function I try in '13 gives me the error message "Your Articulate Presenter project cannot be upgraded to the new Articulate Presenter '13 file format."

Please help!