1. This is something I see shilled for a software title that is spammed so I will not name that software. (It's bad stuff and spammed.)
2. As to ensure, How about Roadkil's Unstoppable Copier? It has an abundance of options to verify and more.
3. NEVER MOVE. Be a rock. I'm not kidding. There are pleas for help recovering files from a failed MOVE. If you don't have backups, that should be addressed first. If you elect not to backup, YOUR CHOICE but beware no one will feel too sorry for your loss.
That out of the way, you can use a fine copy tool like Roadkil and once the files are safe in their new location, Delete the copy you don't want.
So I have 3 drives with me right now.
One is my 1tb that was in my computer until recently.
One is my 4tb which is in my computer.
One is a smaller external drive that holds a previous backup from an unknown time.
I would like to move the everything that is on the 1tb and the smaller external drive to my 4tb (or essentially to a folder on my PC).
What can I do to ensure that everything moves or copies over?
(ex. some stuff won't copy because of long file names, or it's give no option but to skip.)
(Since looking through manually is something I have troubles doing and also don't really have time for)
Thanks for the help (and suggestions).

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