Photoshop: PSD file missing all layers & folders, black background only when opened.
EDIT: TL;DR for those still seeing this after so many years: First, check if you have AUTO-RECOVERY ON.
If not, the file is likely corrupted and can't be recovered. I posted below with more information. Your best bet is to SET UP AUTO-RECOVERY and get started rebuilding your file from scratch.
Since this thread still gets replies 7 years after I posted it:
This is a corrupted file issue. The file data is probably gone.
To have PS to keep backup files: go into Preferences > File Handling > and check the box that says Automatically Save Recovery Info Every x minutes. If you have this enabled already, your work is probably backed up, google how to find the recovery file.
The file may still show a thumbnail and large file size, because the save process failed/corrupted before it updated those attributes, making it look like there's a chance of recovering something (but there isn't). You can browse to the file in Bridge to see the thumbnail (and copy/paste that for reference, if that's helpful).
I've tried checking corrupt files with various recovery tools and plugins over the years, but none have been able to extract anything useful from the file once it's corrupted in this way.
I was working on a file this morning which had several layers grouped into folders, nothing fancy, some transparency. Saved it, closed PS (cs6). Windows (7) was trying to update and wanted to restart, and I do so.
I open the file again later, all of the layers have disappeared, all of the folders have disappeared, and the 'background' layer, which I'd removed, is back, completely black, locked.
The file size is still 315 mb. If I save a copy from PS, it goes down to what you'd expect a file containing essentially nothing would be, a few kb. If I max out contrast I can see a one-pixel strip of noise across the top of the artboard, and everything else stays black.
I assume the update process ruined the file somehow. Wondering if there's any way to recover/revert. The fact that the file retained its size has me hoping there's a way.