This bug is getting very annoying, so I chose to make a new thread about it. The old thread was (mostly) about a different issue. Of all things this bugs me the most (pun intended). I'm now in 5.3.2p3 and I get "Cannot load Atlas [ATLASNAME] During Build/Enter Game. Please rebuild Sprite Atlas." several times a day, always when I change build target and basically most of time I touch any of the sprites I have. It doesn't matter if you run the game, build it or just repack from SpritePacker: the error appears and one or more atlases break. After that point it will always complain about those atlases, spamming the same error hundreds of times when I start playmode in the editor. Workaround is to quit Unity, delete the AtlasCache folder and restart. These wasted minutes add up quickly.. This has been happening since 5.2 days at least, I think it was not in 5.1.x. I'm running Windows 10, I have not seen this on Mac (although I use it only for iOS work occasionally), so I'm assuming it's Windows-only problem. I tried to reproduce this with a clean project for 1.5 hours, and could not make it happen. I copied all my sprites and their settings, atlases are basically the same but no luck getting the error reproduced so I could not make a bug report. Anyone else getting this? Maybe we can narrow things down by searching for common things in the projects / systems this happens on.