Local USB Backup Drive moved to Network Drive ?

Windows 10 Pro Version 10.0.19041 Build 19041

I have a 4TB USB drive I'm currently using for Windows File Backup.
I want to move this to a NAS Drive configuration using a Raspberry Pi using this tutorial:
How to Turn a Raspberry Pi into a Low-Power Network Storage Device

My 4TB USB Drive will be attached to the Raspberry Pi via USB as an NTFS drive with the proper drivers installed on the Pi so that can still be used as NTFS.

Since I already have File Backup data on this drive, will Windows continue to use that data and append to it even through it's over the network instead of direct USB?
Or, will it force me to create a new folder on the 4TB Drive?
Or (worst case), will I loose everything on the 4TB Drive and I have to start over again?

Thank you for your help.

Assuming you are using File History (you don't say), then the files are stored in plain sight, individually, with date & time info added to file names. Once connected via the Pi, the drive will not (or is highly unlikely to) be immediately recognised by the Fh system as 'in use', and you will have to start FH again, selecting it. With luck, FH will recognise the contents, and allow you to carry on where you left off (I forget the exact wording it uses).

However, if it doesn't, you can just let it start again (saving to a different folder you create beforehand). Assuming you are talking about a backup, and not an archive, this should not matter to you, apart from the time it will take to re-copy the current set of files - just sit back and let it run. If, on the other hand, you have files on the drive which are not also on your PC, then you don't have a 'backup' as such, and need to think again.

Sorry, should have stated I am using "Back Up using File History"

If I test this using a USB Drive. Then this really will break the chain of history I have on my 4TB drive. So when I plug the 4TB drive back in (either via Direct USB or Network share), I'm almost positive Windows will force me to make a new backup folder for a new history set - thus duplicating a lot of data already on the 4TB drive and wasting a lot of time and space.

If Windows doesn't seamlessly detect the existing File History backup folder when I move it to a network connection and continue to to File History Backups to it just as before (without creating a new backup set), then I don't want to do this. I'll just keep plugging and unplugging my 4TB USB drive into my PC every time Windows nags me to do so.

But if I try it, either with my current 4TB drive or a test USB stick on the network, and it doesn't work (ie: it forces the creation of a new File History Folder), then even if I go back to direct USB connection, it still won't use the original File History Folder and I'm still screwed.

Hope someone has already tried this and can tell me what Windows will actually do.

Thanks.

I believe that if you switch to a usb stick (on reflection I don't think it will let you use one), then re-connect to the 4TB drive, it will pick up where it left off. Do you have another PC you can test this on? I may just try it myself (I have done it before, but ages and many W10 versions back)...

OK. I set up another laptop and used a USB Flash Drive (32GB) formatted as NTFS and started a backup (which Windows did allow me to do - yay!)
Canceled the backup after some time, so I could move it to my Raspberry Pi and test.
And after setting the FileHistory folder in my Samba 'backup' share, Windows recognized the User Folder and PC Name Folder as an existing Windows File History backup and asked if I wanted to continue using it to back up to.
So, YES, it does allow you to migrate a USB attached HDD to a NAS and continue using it without starting over, or erasing.
Now I just need to do it for real on my PC!
Thanks for everyone's help and suggestions!

- - - Updated - - -

NOPE!
SOMETHING IS WRONG!
I just cancelled the backup to the network drive.
The previous backup was 13GB done via direct USB, but now it says my backup is only .99GB
Crap

- - - Updated - - -

Ok. Doesn't look like it will work. And the continuity of the File History backup is lost everywhere.

I did a local File History Backup to a fresh 32GB USB Drive.
Canceled after a few minutes and noted it has backed up 1.8GB
Restarted the backup and then canceled again after a shorted period and noted the backup was now 2.4GB - so it did append backup data to an incomplete backup.
Then moved the USB drive to the Raspberry Pi and selected that NTFS network share in Windows as my new File History Backup path.
It saw the existing backup and asked if I wanted to continue using it. However, it warned me that File History Backup was not current and that I would need to find the Current backup if I wanted to restore current files.
I went ahead and selected the existing backup and started the File History backup again.
After a few minutes, I cancelled and noted that the File History Backup size was only 805MB
Checking Properties in Windows showed the total space usage on that network attached Drive was over 3GB. So it did not delete the old backup, just started a new one instead of appending to it.
Took the USB Driver off the Raspberry Pi and placed it back into the USB Port on the PC and selected it to do File History Backups to.
Windows recognized the existing File History Backup and allowed me to select it to continue backing up to it. However it did NOT warn me that the backup was not current.
I resumed File History backup to it and after a brief time, I cancelled it.
The File History Backup was now only 400MB - so, not only did it not append to the set it created when used as a Network Driver, it also did not use the set created originally as a local attached USB drive.
I also tried to restore personal files, and it only showed ONE set (presumably the most recent).
So it looks like once you move a drive, the data is still there, but there is NO WAY to restore it IF you use the same File History Folder as the previous backup.
This sucks

Unfortunately, by moving the drive from a direct connection (USB) to a network connection appears to invalidate the previous File History backup.

While Windows recognizes the folder structure as a File History Backup, it ignores those files and creates a new backup - starting a complete backup again instead of appended new/changed files to the previous backup.

And once Windows has done that, I do seem to be able to get to the original File History Backup files for restoring.
argh

I thought I already made this comment, but either I did not, or it got 'lost': when testing the re-connection of an existing backup, you really must let it finish the first one - stopping it part-way is asking for disappointment. I can't guarantee that it will work, but I would say don't give up yet. To make that practical, choose a small sub-set of your total data to backup.

When you transferred the partial FH USB to the Pi, did you turn off FH first before unplugging the USB? If not, do so.

dahai8 said:

And once Windows has done that, I do seem to be able to get to the original File History Backup files for restoring.

Do you mean 'do not' ?

I'm off to try my USB drive on another PC...

mngerhold said:

Do you mean 'do not' ?

Sorry, yes, meant 'do not'. I type slower than I'm thinking so words get dropped

Thanks.