A fix for the Workshop download fail (Steam_AppUpdateError_42 / MISSING DOWNLOADED FILES)

[Junkman Cicero]

It has come to my attention recently that many people online have been reporting an issue where Steam has failed to complete downloads and, depending on whether you're in Big Screen mode or not, the reason will either come up as 'Steam_AppUpdateError_42' or 'MISSING DOWNLOADED FILES'. I only found this out myself when it happened to me. I was lucky enough to find a solution to this after some searching. I figure I ought to put it out there so that others might be able to find it as well. I understand there may be other related issues which this may not fix, hopefully that's out there somewhere as well.

From DeejC, via CEASTY YUNT:

Delete all items in your steam directory apart from your steam.exe and steamapps folder. When you launch steam again you'll have to log in, and it will download all the files you just deleted again and this issue will be fixed.

Just note that you will lose screeshots if you do this, just relocate them to another place on your drive if you want to keep em.

[thebookman10]

I deleted everything apart from steam and the Steam-library folder and now it wants me to download all my games again even though the files are already on my computer.

[Junkman Cicero]

That's weird. Have you tried verifying the integrity of the game cache?