Tl;dr:
Back up your save files. Something went wrong, saves are getting corrupted. This guide explains how to perform a backup.
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Ever since u237 went live, more and more people have been reporting save files becoming corrupted and deleted. While saves becoming corrupted is nothing new, the number of reports of saves becoming corrupt have skyrocketed as of u237. It has now been well documented in the community as a real bug, and should be taken seriously.
Starbreeze has even attempted to address the issue. However, this announcement about a save corrupting bug has been relegated to the Steam Forums only, most likely to not rekindle the flames of the current drama. Only announcing the issue in the Steam Forums does very little, as users only go there looking for answers after it's too late for their save files. The locking of the payday subreddit has also hampered spreading the awareness of this bug, and it's become a bit hard to spread awareness.
I'm now using the site notice box to help spread awareness of this bug, since we do receive a decent amount of traffic. Once you close the box it will always remain hidden on the browser you used, so it shouldn't get in the way as soon you close it once.
Edit: Sitenotice apparently only works if you open the recent activity page. That's not exactly useful, so I may end up using something more... obtrusive. Sorry.
