I searched for this topic and found that it was dealt with a year ago.
This is what I found:
When you try to install Ubuntu on the same Windows disk, Ubiquity is stopped on the Updates and other Software screen. So far the solution is to open the GNOME Disks application, and unmount and mount the Windows boot partition several times. When rebooting the installer displays a message that partitions are mounted and if you want Ubiquity to unmount them. When answering Yes, the installation continues.
I did not understand the work around. The reply poses more questions than answers.
Sadly the problem has not been dealt with and still remains on the latest version.
Zorin clearly not for me! Back to Windows. Sorry guys.
