A Terrabyte of files copied to a win10 drive have disappeared.

horses · 24 Jan 2020

So I've got a very strange problem with files disappearing.

I've bought a new hard drive for my sister and installed a new windows 10 on it (x64 home, whatever version the installer tool downloads these days). I unplugged the new drive from her computer, plugged it into mine (x64 pro v1909), and copied all her old files onto it. I confirmed that her files were still readable from the new drive, unplugged it from my computer, put it back into hers and booted it up.

The terrabyte of files I copied to the drive are gone. Her Windows reports that the drive is still empty, save for the few gb win10 occupies. I put her drive back into my computer, and the files are still gone. My windows reports that the drive is still half full anyway. A file system scan and repair corrected the used space back down to just a few gb. I tried copying a few more files to it and booting it up in her computer again, and the new files disappeared again.

I tried updating her windows and running a file system scan and repair, but both failed. I tried restarting, but her windows failed to load, giving an NTFS file system error. Probably because of the scan and repair i did on the drive while it was in my computer, but it's a little odd that it would boot the first try after that, but not the second. I Reinstalled and fully updated her windows and it still works fine, so I don't think it's a problem with the new hard drive. And I didn't sign in with any microsoft accounts, so I don't think OneDrive could have anything to do with it.

So this is seeming like it's some sort of win10 security system? It's like it keeps a backup of the master file table and overwrites any changes whenever it boots? Whatever's happening, can I make it stop?

I can still transfer the files via a usb drive if I have to, but I'd really like to figure out what's happening here - even if only to make certain that it's not the new drive's fault.

mngerhold · 24 Jan 2020

Very much a long shot, but are either of you (knowingly or otherwise) using fast startup? If you don't know, a web search will explain how (and maybe why) to turn it off - under power options. With f-s turned on, a normal shutdown saves the system state in a form of hibernation, and reads that back on start-up. If drive contents have changed in between, Windows can get confused. Rather oddly, if f-s is on, only a re-start actually shuts down then restarts the computer. That won't help in your case, so turn f-s off if it is on and try again.

horses · 27 Jan 2020

Nice, looks like that did it. And it even explains why the drive booted the first try after I'd messed up the file system, but not after restarting.

Samuria · 27 Jan 2020

Its a bad idea putting it into another pc any files you copy would have you as owner and you can have problems accessing them on the other pc and it may change somother settings

horses · 27 Jan 2020

Thanks, I'll keep that in mind. I've dealt with file ownerships and permissions many times in win7, but I only recently switched to 10 myself, so I'll make sure to check carefully that everything's accessible. If there are any problems I'll just copy via usb.