Welcome to the club!
Lesson learned: NEVER decide to "clean up some old files" at 4:30 on a Friday afternoon. You WILL look for shortcuts and it WILL bite you on the ass.
This was back in the mid-'80s, while I was using/adminning Unix boxen with a "Beginner's Guide to Unix", or some such, in hand because -- while I was the Art Department's tech-geekiest member -- I was not a programmer. Fortunately we were a beta site for the machines so;
A -- Having called the vendor Friday to announce my stupidity, our rep was in on Monday morning before I even got there, re-installing the system and recovering the work files, and;
B -- A short time later, the company updated the software to include a GUI for admin tasks, taking the command line out of the hands of fumble-fingered amateurs. (Gee, I wonder what inspired THAT decision...?)