hey, buy google drive desktop, (or some other cloud that auto backs it up) and, then pay for whatever size you need to handle your game folder and related folders.
this saved my butt. i went through my recycle bin in my google drive and found the asset blueprint that i deleted and then clicked “restore” and it redownloaded it back onto my computer, and then plopped it back into the folder it was originally at.
10/10.
also, never set any cloud service to automatically remove items from the recycle bin.
it might be too late for your file you lost in 2015, but it isn’t too late for anyone who just messed this up today and might not want to mess it up in the future.
(it’ll take time for your game folder to backup. and of course, always be careful on deleting items, as you might have found out today that you deleted something you shouldn’t have)
AND ALSO, use a private GIT source control. i’m using a free one, and that is seriously helping with me keeping track of changes i make in programming, and also backing up and being able to revert non-binary files. (binary files are art, and non-binary are generally programming)
take the time to set those up properly and to learn how to use them. even if your a solo devvy, the time you will save will outweigh the time you would otherwise loose.