Stop Office BACKUP THIS DOCUMENT prompt

The folder redirection you show is normal -- that is what happens when selecting the Onedrive "backup" option; the selected user folder locations (and their current content) are moved into the Onedrive folder, so they get synced as part of Onedrive.

No, the redirect was done manually at the time I first set it up (many years ago). Back then, OneDrive did not have a "backup" feature, just the normal "sync".

Also, my "sync" is not malfunctioning. It is working just fine. It's the "backup" that is the problem because it seems to want to backup the local folders (i.e. "Documents" not "OneDrive/Documents"), and I have nothing in those local folders.

OneDrive is fully aware of folder redirection. If your Documents folder initially resolves to the default location (i.e., c:\users\yourname\documents), and you subsequently turn on "backup" for Documents, OneDrive will physically move the contents of c:\users\yourname\documents to the Onedrive folder (e.g., c:\users\yourname\OneDrive\documents). I don't know how OneDrive reacts -- or how confused it gets -- if you turn on Backup *after* having already manually redirected and moved the content yourself.

I did not mean to infer that Onedrive redirected your folders -- I fully understood you to say that you manually redirected them prior to activating the OneDrive "backup" options. But the location to which you redirected is the same location OneDrive "backup" would use. That may be a source of confusion, since OneDrive expects to redirect and move the folders itself when Backup is enabled.

The folder redirection you show is normal -- that is what happens when selecting the Onedrive "backup" option; the selected user folder locations (and their current content) are moved into the Onedrive folder, so they get synced as part of Onedrive.

No, the redirect was done manually at the time I first set it up (many years ago). Back then, OneDrive did not have a "backup" feature, just the normal "sync".

Also, my "sync" is not malfunctioning. It is working just fine. It's the "backup" that is the problem because it seems to want to backup the local folders (i.e. "Documents" not "OneDrive/Documents"), and I have nothing in those local folders.

Even with the Backup options enabled, it still "nags". I have them all enabled (except for the "Desktop"), yet I still get the regular "nag" message.

Maybe there is some other configuration or setting missing that I don't about, as it always shows "0 KB Backed up".

EDIT: Maybe it is because I redirected all my OneDrive folders on to my local folders. In other words, my "Documents" is actually the "OneDrive/Documents", etc.

Decided to switch to FreeOffice good enough for my needs & will downgrade to Office 365 Basic.

Maybe late but I found the solution at this link:

how do I stop all my excel files from being saved to the OneDrive - Microsoft Community Hub

in file, options, save: remove the tick on the first box that says save automatically on the cloud ...

Unfortunately, that is not what this thread is about so that is NOT a solution. That setting controls auto saving, but has NOTHING to to with the “backup” option. Regardless of that setting, the “nag” banner will still be displayed if the “backup” options are not all enabled.