Copy then Delete, Don't Move

Yesterday I wanted to get three exams done for my online course. I only got one done, but it was the toughest test yet. Also the exam spanned two chapters instead of one.
The weather here has been good for sleeping, nice and cool breeze from the north.
I've been up for a while, the dawgs come crying for a walk. But I like being up.
On my laptop my hard drive was almost full. So I started moving my music and movies to an external drive. I started getting these messages like: "Cannot Delete Folder: Music, folder is not empty". Well I looked, and the folder is indeed empty, but there is no new folder on the other drive. SO whwat that means is, the computer moved the files from the folder, then couldn't finish the moving the folder, so it deleted what it thought was an incomplete folder. In other words, I lost the files in the music folder, which were the songs. Later my external drive quit completely, and was really hot.
So I moved my files to a backup drive, and lost them. Hence the title, copy then delete, don't move. If I had copied instead of moved, I wouldn't have lost my files.
There's hope yet though. I can turn the drive on after it cools, and get the files off till it screws up again. Bit by bit....