"Another installation is..." There is NO "other installation" !!!!!

I have just bought Photoshop Elements 2020 and downloaded the trial while waiting for delivery from Amazon. Started to install, through administrator, and it refuses to install. No matter WHAT I do it refuses saying theres another installation - THERE ISN'T !!!!!!!!!

This is driving me up the wall, tearing hair out. I tried to UNinstall my Photoshop Elements 11, and it won't even properly uninstall that for the same reason. 

Anyone who knows a fix, please let me in on it !