Stuck on 'Preparing to move...'

[rexone]

I'm just trying to prep my old iMac ahead of migrating to a new iMac Pro & this problem is driving me nuts.
I still use iPhoto and want to transfer that library to the new machine so that it can do a totally clean conversion to Photos. As much as I despise that app I will need to migrate so now is the ideal time.
Problem though... in my Pictures folder there are 3 x Photos libraries because of the times I have tried Photos.
These are named Photos Library.photoslibrary, Photos Library 2.photoslibrary etc.
My thought was to drop these into a folder & zip it to keep them 'hidden' when I migrate so Photos doesn't latch onto them instead of the iPhoto library.
Libraries number 2 & 3 have dropped into a new folder no problem but the original library just sticks on 'Preparing to move to...'
I should add the new folder is in the same main folder that they are so I'm not moving to an external disc or anything. It should take, well, no time.

Anyone have any suggestions for what is going on here? And, more importantly, how to fix it?

 

[Fishrrman]

What I would do:
1. Download CarbonCopyCloner or SuperDuper. Both are FREE to download and use for 30 days.
2. Created a cloned backup of the old iMac (either of the above will do it).
3. The cloned backup can be "mounted in the finder" on the new iMac. You can then "go in manually", and copy folders/files to your new iMac (with its NEW account) as you wish.

NOTE:
If you do this, when you first mount the backup drive on the new iMac, you must do a "get info" on it (click on the drive's icon in the finder and hit "command-i" (eye). Then at the bottom of the get info box click the lock icon and enter your administrative password (for the new iMac). Then put a checkmark into "ignore ownership on this volume".
This will overcome "permissions problems" that might arise between your old account and your new one.