Contents of folder have disappeared Twice in the last week the entire contents of a folder have disappeared when I start up my computer. The folder contains over 100 GB of files, including all my work files. It's the first folder in the root directory of my hard disc. I'm running 10.9.5 on a 27" iMac. I have been able to restore all the files using Time Machine, but it's time-consuming so it would be much better to solve the fault that's causing this in the first place
This was a bug in a recent Adobe Creative Cloud update (version 3.5.0.206), causing the first folder, alphabetically, to be deleted from the user's boot drive.

It was first noticed by Backblaze, as their backup structure creates a folder that is often at the top of the list, .bzvol

As your folder was called Workwith a space at the head, that will have filed it to the top instead of any 'dot' folder.

Backblaze recommends creating a new folder called .adobedontdeletemybzvol by typing the following in Terminal sudo mkdir /.adobedontdeletemybzvol, however, this wouldn't work in your case, as space will file above a . 

The bug has been fixed &amp; a new update released by Adobe, but in the meantime, creating a new folder starting 'space a' would be safe… maybe adobedontdeletemywork would be appropriate ;-)

Refs:
ArsTechnica - Warning: Bug in Adobe Creative Cloud deletes Mac user data without warning
Backblaze helpdesk - .bzvol is missing