Secondly, is it actually necessary to have the target drive be completely empty? I have files on it that I don't want to remove, but are not critical (in case they get deleted somehow). But is it a necessity that the drive be totally empty? It would save me many, many hours re-downloading my Steam library, for example.
Thanks in advance, I hope you can answer my queries!
It is not absolutely necessary.
I apologize now, I do not want to sound patronizing, just lazy , but the fact is that telling you geeks (some of you have never done anything like this) to be sure the target disk or partition is empty, I have saved a lot of unnecessary answering to posts with issues.
In fact you can even have the user profiles from several Windows installations on the same target disk. I've had a triple boot Windows 7 / 8.1 / 10 system where the user profiles of all three operating systems have been relocated to same disk. It requires some tweaking but it can be done.
Based on the above, this is "the official statement", the scenario I promise to work and promise to support and give assistance when something does not work as expected:
- Be sure to backup all your personal, important data from the target disk to a safe location and finally make the disk empty
- If the above is not possible, be sure move all files from the root of the disk to folders (when opened in Explorer, the disk should only show folders, no files)
- Be sure the target disk does not contain any system files and folders from any other Windows installation
- Be sure the target disk has enough space free for your Users folder
What the above means: If you have no external storage to backup the disk and make it empty, you proceed at your own risk. It will work, though, in most cases, this is just me being cautious. If (unlikely) something happens, I will not accept responsibility, being accused of your lost Steam library :)