Yev from Backblaze here -&gt; sorry! It took us all day to figure out what the hell was going on. Kept getting folks writing in, when nothing had changed on our end. Our Mac dev probably left a dent in his wall from trying to figure it out. We finally narrowed it down to the ACC update. Then realized that WE were affected more than most apps simply because .bzvol starts with a &quot;B&quot; and so a bunch of our users were affected. Likely if a user had a hidden folder with data in it named anything &#x2F;.0-&#x2F;.a that folder&#x27;s data could have been removed as well (we tested this). So hopefully they had a backup&#x2F;hidden folders are rare and few were affected.