I had this problem also on a 1 year old computer with a SSD. In my case I was working in lightroom and it just closed on me as I was retouching a simple photo.
I tried several times your method but failed everytime. But I thought about the problem and finally copied "Light Room Catalog -2", pasted into the Backup Folder, then renamed the Folder to "Light Room Catalog -3", then copied the file that was in the origional "Light Room Catalog -2"folder, and pasted that into the Folder holding my previously pasted copied & renamed folder ("Light Room Catalog -3"). So that folder now contained the "Light Room Catalog -3" Folder plus the file that was in the origional folder as well. Yes... that file should be in 2 new places now, once in the main Backup Folder, and a 2nd time in the "Light Room Catalog -3" folder in the main Backup Folder. Hey crazy... but it worked after that.
I hope that makes sense.
Note: I had the same thing happen on my other power horse a week ago. Only then I used an older data base. Me thinks it was not the SSD's but a possibibly a windows or LR update. I have been doing this since Lightroom 2 as a active Professional with 100's of thousands of images and never a burp... and to have it happen on 2 different laptops within a week with SSD's... I say its an update.