Usually when I see this issue, it's one of the following:
- The iTunes backup folder is missing, damaged, or has incorrect permissions.
- The iTunes backup folder was previously redirected to an external drive that's now disconnected (a fancy variant on missing really :))
There's two locations for the iTunes backup folder, depending on whether you installed iTunes direct from Apple or via the Microsoft Windows 10 store.
Direct from Apple:
- In the Windows search bar type
%appdata% (with the percents) and press return/enter. A file browser window will open to the Application Data folder.
- From there, navigate to Apple Computer -> MobileSync -> Backup.
From the Windows 10 store:
1. In the Windows search bar paste
%userprofile%\Apple\MobileSync\Backup and press return/enter. A file browser window will open to the iTunes backups folder.
Do you have one or both of these folders? I usually like to start by recommending renaming the existing Backup folder and making a fresh new folder named
Backup (must be named exactly Backup) and seeing if that helps.
My blog post about how to find the iTunes backup folders:
https://deciphertools.com/blog/where-are-iphone-backups/ (Obvious disclaimer: I'm linking to myself as a reference.)
I have more suggestions about fixing an error making a backup here https://deciphertools.com/blog/fix-iphone-backup-corrupt/ under the section "iPhone Backup Corrupt or Not Compatible - Can't Back Up" There's tips about errors restoring a backup as well, but please don't try those for this issue!