Mcreator isn't working, is this the reason?

my Mcreator isn't working, and I know you need to have to previous version uninstalled for it to work, when it tries to uninstall the previous version it does, but not really since I have a version installed from a long time ago and it is in the downloads folder (version is over 2 years old, back when it did that) instead of the user/program folder meaning it doesn't uninstall it. Is this the reason it doesn't work?