Very interested in your findings and what can be done to protect a system from what every you find.

Oh wow. That sucks. If you're saving to Google Drive it does versioning for you. Open it in the web-browser Drive and you should be able to see previous versions even if files have been changed/deleted.

Well, after running 4 different virus scans (of varying intensities), running scandisk, etc. multiple times, even reloading into safe mode with only essentials running, haven't found anything but a cacophony... My suspicion(s) is/are 1 or more (or all) of the following:

1) the system in question contracted an undetected (as yet) virus or other malware

2) Somehow, Google Drive backup was disabled Sunday morning around 5am
    I have my working folder with the main file I work on, then every time I shut down, I make a copy of it with a timestamp
    and copy that to my "staging" folder so that google and one drive can pick it up just so they don't inadvertently try to grab while
    I'm working and cause problems.

3) Assumption is the Mother...
    This morning when I made my copies (or thought I did), I had just drug my timestamped backup to the staging folder as well as the
    two USB drives - then went and got in the shower while that was working. When I came back, the screen was on the desktop.
    Being in a hurry, didn't think anything of it, just grabbed my USB drive and went...

4) According to system log, Windows did an update at 7:09 am this morning and rebooted the machine - which was right about the time I was in the shower, thus it shut One Drive backup down as well before rebooting

So best guess for now, Windows rebooted in the middle so it never copied the file + OneDrive getting deactivated for the update + Google Drive not running so nothing had been uploaded there since last weekend meant nothing backed up... But still haven't figured out why my working file regressed back to last week or why the timestamp copy in my working directory was also regressed.

At this stage, don't have the time to dig deeper since this is the app I planned on bringing live for beta at the office (at least the first part) this week because we can't go another year with our existing software as it keeps having to many conflicts and miscalculations.

Welcome to Microsoft.
I had my 3 office computers update and reboot automatically.  I have update and reboot turned Off. But Microsoft did it anyway.
Your cell phone will do this same thing.
You wonder why cell phones are free now and Microsoft Windows.
Control Control.

Donald I have been using a program called FreeFileSync to sync my working folders up to my backup USB.  Within a drive, windows defaults to move instead of copy when dragging files.   This may not be the solution for your problem but it does make syncing a one button event, once the application is open.  This also allows you to see a summary of everything that has changed and preserves the original copies in the working folders.  It is pretty quick and has been able to do everything I have needed.

Donald I don't think this was corruption or malware. As awful as this feels, this looks like a perfect storm of timing, assumptions, and Windows being Windows.

A few important points for everyone reading this, because this is a really good cautionary tale. Malware almost certainly did not do this. Modern malware doesn't quietly roll a database back exactly one week across every backup location while leaving everything else intact. If it were malicious, you'd be seeing obvious damage, encryption, crashes, or missing files, not clean and consistent regressions. This also doesn't look like Access corruption. Corruption usually shows up as broken objects, errors, or files that won't open, not a clean loss of recent work across multiple locations.

What this really smells like is a copy operation that never actually finished, combined with a reboot at exactly the wrong time. Drag and drop copying is risky, especially when you're tired and in a hurry. Windows does not always make it obvious when a copy is interrupted, paused, or never completed. Walking away during a copy, then having Windows Update reboot the machine, is more than enough to leave you with the last known good version everywhere without throwing a big warning in your face.

Cloud services like OneDrive and Google Drive are sync tools, not true backups. If the updated file never actually made it into the staging folder, then those services simply synced the older version. They didn't fail. They did exactly what they were told to do.

The big lesson here is this: a backup you didn't verify is not a backup, it's an assumption. If you don't open the copied file, check the timestamp, or confirm the size changed, you don't really know what you have.

This is also where a real backup tool would have helped. Something like Macrium would have given you a safety net beyond simple file copies. I actually did a test restore today from one of my Macrium backups, and it's pretty slick. You can pick an incremental backup file and Macrium will automatically pull whatever it needs from the last full backup in the same folder. It then mounts that backup as an extra drive letter on your system, so you can browse it just like a normal hard drive and click and drag files out to restore them. In a situation like this, being able to roll back to last night's known good state would have been a lifesaver.

I know this doesn't bring the lost work back, and that part really sucks. But I'm confident this wasn't anything malicious. It's a painful reminder that manual backups and cloud sync give a false sense of security, especially when Windows decides to reboot on its own schedule. I'm probably going to use this exact scenario as a Quick Queries topic because it's something a lot of people think they're doing right until the day it bites them.

Thanks, Matt I have been thinking about doing something like that for a while... Will be a weekend project to get and setup

You can always write a script or batch file that makes a backup copy first, ideally with a timestamp. I do something similar when I record videos. I record everything into a single folder, then click a button that moves the files to another computer where all the processing and AI work happens. I have lost files during that network transfer before, so the very first thing my script does is copy everything I just recorded into a local temporary folder with a time stamped name. That way I know I have a safe copy before anything else happens. That might be a good approach for you too.

Yeah, Richard, that's pretty much the conclusion I came to when I reviewed all the logs and everything I could find. Hence #3, in my list above (and why I didn't finish the phrase out of respect to you and the rest of your site's viewers). Sadly, essentially, important review is something else you've mentioned in your blog last year to the effect of slowing down and being sure it's right versus just flying thru and assuming it works as expected.

Unfortunately, of late, I all too often have to remind myself of that between 3 (overlapping) full time jobs + general home responsibilities + taking care of my mother's medical necessities as well, I'm always trying to do 5 things at once.

Donald I'm really sorry you're dealing with all of this at once. Losing work is bad enough, but piled on top of multiple jobs and caring for your mom, it's completely understandable how something like this could slip through. This wasn't carelessness, it was exhaustion and terrible timing.

You're not alone. I had a similar gut-punch years ago, back in the late 90s. One hard drive, probably a massive 2 GB at the time, had my entire business on it. Database, customer info, everything. No backups. Gone. I spent two or three days pulling my hair out and seriously considered paying one of those data recovery companies a couple grand to try to save it. I ended up rebuilding most of it from a month-old copy of the database I had on a floppy disk, old emails, paper invoices, and whatever scraps I could find, but it was brutal.

That week of frustration is exactly why I've been borderline obsessive about backups ever since. It's also why I just spent a full day recently reworking my own backup setup with Macrium. Not because I didn't have backups before, but because too much of it was manual and assumption-based. My goal now is to turn backups from an occasional all-day chore into a quick weekly check that takes ten minutes.

Painful lessons stick, unfortunately. But they also make us better long-term.