windows 10 (October 2018 update) (version 1809) deleted all my files

good luck with that I ended up having to wipe my system and go back to 1803 version. I ended up having to download and reinstall over a terabyte of software. It's a good thing I keep all of my other files like my movies and my music and my document on separate hard drives in my system. I think Microsoft should have to pay everybody whose system they screwed up and cost them data time and money. Because I will have to lay out and extra cost for the data cap I have to go over to get back everything I lost.

That's right about making backups. Here is the official MSFT explanation...

https://blogs.windows.com/windowsexperience/2018/10/09/updated-version-of-windows-10-october-2018-update-released-to-windows-insiders/#yRlroHtaQVHofZu3.97

Updated version of Windows 10 October 2018 Update released to Windows Insiders

It's an issue of Known Folder Redirection (KFR). C**:\users<Username>** is normally where the "known" user folders are kept, like Desktop, Documents, etc. But they can be moved elsewhere, like to OneDrive or to another HDD. Many did redirect them prior to the 1809 upgrade. After redirection (no matter to where), if files were left behind (or subsequently added to) the known folder (i.e., the original location) - they got deleted by the 1809 update.

That's the sad story. I was spared because my redirections left nothing behind. The size of files & the capacity of OneDrive had nothing to do with it. They weren't being moved - just plain deleted. Excellent to have backups.

I have been perusing the tech journals, and noticing that Microsoft seems to be pushing the testing back on the Insider, and will undoubtedly employ "go slow/slow-ring" QC on future updates. The point missed, however, is this: Feature Updates, however regular (monthly, quarterly, semi-annually), are just that: Features, not core O/S functionality patches. My vote would be to make the "optionality" of FUs (or in this case set the 'FU bar' lower ;) a leetle more visible, for those IT admins who lack time for full "Insider" regression testing every six months. Going to this extreme shouldn't be a Reg Hack or even a System Center Configuration Manager push to the enterprise to slow the flow of Feature Updates (up to 365 days).

Also, speaking for rural folks that get their internet from a dish and are metered or throttled every six months during download of a 4 GB OS "pull" by several unknowing machines in the household, it is a very real imposition, even if I don't lose any data, to watch the latest "Better Call Saul" in jerky Low Def.

If they must be mandatory, clearly just setting a bit flag for severity amongst "Insiders" will not be a silver bullet, and use of the "free resource" of Insiders by Microsoft may be a concept worth reconsidering. Let's face it: This isn't the first time in Microsoft history that a "cool feature" ended up causing a whole lot of bad days for IT pros and end users alike!

I also had my files blown away on one HD and my SSD doesn't seem to work properly. I've tried moving the SSD around to other SATA slots and see if it is a cable or something else and it seems to work OK, but not in SATA 0. 

One issue might be a coincidence, but both things happening at the same time is a bit much for me to believe. This is on an HP i7 Envy Phoenix desktop that was working fine until this upgrade. I do have these files backed up, but need to get a working system!

I had to boot off a windows to go USB to even start the diagnostic process from a GUI and I am still stumped as to what is going on.