So, today, while going through my code, my computer crashed. It's an old computer from 2011 that I haven't the heart to replace. When I loaded up Unity, I got over 1000 errors, all talking about the GUI not being able to load. My scene was gone. I double clicked my scene, and it was empty.
I had no backup.
All my assets were fine, but it was extremely disheartening. Looking up support, it appears my scene got corrupted and is gone. I might've been able to save it if I hadn't loaded Unity, but I didn't know. Unity stores a backup scene to the last it loaded. But once you load unity, that backup is overwritten.
Everything I had was UI, luckily. No custom settings or anything. I think I had some fonts that were not the same, so this will give me a chance to get the measurements correct for everything. My scripts were doing all the settings, so I literally just have to drag the UI into their slots once I have them up, and it'll work as plug and play.
So a lesson learned. Back up your work. Use version control. I had no back up to this scene. I didn't think it would happen to me. Luckily it was stuff that I can reproduce in a day, and not my code.
This is really unlucky, and i feel for you.
Hopefully though its also an opportunity. I recommend installing a good cloud based backup software such as crashplan pro which is $10 a month per machine, with unlimited storage space.
I also recommend using git or perforce for your version control, but store graphical assets separately if you go with git, as git isn't very good at storing large binary blobs unless you use for example the git LFS addon.
I went through the same experience as you a few years ago when my phone was stolen and i'd been a stand-out against cloud software, cloud storage, and backing up my photos to the internet, until this happened. As part of the experience i re-thought my entire backup strategy and now have backups of my backups.
MOST IMPORTANTLY THOUGH, test your backup and restore process regularly. Many people set up a backup, then leave it and assume that's it. If you don't know you can restore from it, you may be wasting time, resources and money. Have a schedule, and test a restore of a simple file, e.g. an image or a model, every 6 months at least. Pick that file at random, and know what you expect back. If anything doesn't work, make sure it's fixed before you continue with it!
Good luck and hope you get everything back how it was soon!