Okay, so currently I am very confused and furious because I believe my sketches just got deleted... So I just got invited to use the Web Editor and I was trying to move the folder with all my sketches into the Downloads section on my Windows PC (running Windows 10) and I went to look for the folder in the Downloads section and it doesn't seem to be there... And the reason for moving the folder with my sketches in it was because I wasn't able to compress the folder directly from "Documents" so I moved it over to "Downloads", to see if I would be able to compress it from there. And when I opened the Arduino IDE and went to File -> Sketchbook, none of my sketches were there ...
So please imagine having my problem right now, and please help me figure this problem out because I know for a fact that any Arduino user would not want to lose all their time spent sketches that you worked very hard on.
It is expected that the files will not be shown in sketchbook from the IDE anymore - you moved it out of (documents)/Arduino, which is where the IDE looks, so of course the IDE didn't find any sketches.
Windows won't delete files when you tell it to move them, so if the folder isn't in downloads, you moved it somewhere else (probably you slipped with the mouse - I've done that). Use the windows search functionality to search for the name of a sketch to find out where you moved them to.
And, in the future, keep a backup of your sketches! (like all of your other valuable documents)
I put everything that matters into a git repo (most of my sketches aren't in the sketchbook folder, which is fine, you can just open them like any other file) and keep it sync'ed with github (in a private repo if appropriate). I highly recommend this.
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