|I'm sure none of us will sulk if we don't get chosen for Best Answer. It's done now so I'd just leave it - you shouldn't get any more reminders.|
The web is littered with request to do just what you are asking but with no definite answers. If you are sure you don't need anything that is on that drive, and you don't mind taking a chance with it, then try this:
With the Seagate Replica drive plugged in, find it in "Computer" - making quite certain it is the right drive. Right click it and choose "Format". In the window that opens, choose the NTFS file system, then Quick format, then Start.
Unless it is partitioned some way it should work like any other drive afterwards. If it then start backing up the C drive again (or it won't let you format) then we seem to be stuck. Seagate insist their customers use it the way it was intended and give no guidance about using it as a normal HDD.
Always pop back and let us know the outcome - thanks