Data files revert to previous versions after restart

For the third time in a week, Windows 7 has replaced some of my personal data files with earlier versions, without my consent, following a restart.
I'm talking about my outlook Data file (outlook.pst), my Quicken data files and a few others. Files are located in different places, but mostly in my Documents folder.

There are no errors, no crashes and no warning whatsoever.
I just restart the PC and suddenly my data files are overwritten with sometimes days old versions. The first time it happened I assumed that maybe I hadn't properly saved my document(s), but then I noticed it actually WAS replacing current files with earlier versions. I would enter a few days worth of transactions into Quicken, save and even backup the files, only to have it revert back to a file that was saved two days ago after restarting the PC, causing me to have to re-enter all those transactions.
Same thing with Outlook - I could add/change/remove appointments in my calendar, only to discover that it went back to an earlier time after the next restart, all changes made would be lost.
Just a simple reboot is all it takes - the last time I had to reboot to update a driver.
This is completely unexpected & unacceptable behavior. What would cause Windows 7 to do this?

Sorry to dig up an old thread, but I can't find anywhere else this has been discussed.

I've had this exact same issue... Windows 7 just reverts files to previous versions, primarily System-related files such as the Start Menu shortcuts. My System Restore has always been disabled on all drives, and I've never set up a backup, so neither of those can be the cause.

This happens occasionally on my home PC, and just happened to me for the first time on my work laptop... a couple of weeks after installing Visual Studio 2010, the start menu rolled back, and now I have no shortcuts to VS on my start menu.

My laptop is suspended every night at the end of work, but my home PC is never suspended, and rarely restarted.

I haven't had personal data files overwritten (that I'm aware of), but I don't keep my documents in the 'My Documents' folder, so maybe that's an answer for others experiencing this.

How am I supposed to trust an OS that overwrites files with older versions without warning, consent, or reason??!? This never happened in XP.

Has anyone found a cause for this, or opened a ticket with Microsoft?

I was wrong... it didn't just wipe out the start menu shortcuts, it completely wiped out VS2010. Unbelievable.

What concerns me the most is that it seems overwritten (reverted) files also include my personal data files.
I could see if maybe only system files were being affected (ala System File Checker) but WHY would an Outlook or a Quicken data file be overwritten with older versions?
Leave MY files alone MS!!!

Back up your work frequently. Like every time you make a change to your work. Don't use Microsoft folders, e.g. the desktop or My Documents to store anything.

This is the kind of crap that makes me so angry with Microsoft... they're trying to be overly controlling of the OS for my own good... it's impossible, and when they screw it up it's at the expense of my data. Just be an OS!!! Don't automatically roll back ANYTHING!!!!!!

FYI: I have Windows XP Home edition w/SP3. I'm having the same problems noted here. It seems to effect my Quicken data, Outlook Express email, and even my screen saver photo was involved this morning. I guess I will disable the backup and restore functions and see what happens.