Follow up. Exchanged the Seagate for a WD. Hooked it up and after 3 hours, I was still getting the format screen. Then thought maybe it had to be the only ehd attached to the Hopper, so I disconnected the other ehd. 10 minutes later, the new ehd was formatted,
Moral, the new ehd must be the only one attached for it to format.
Moral, the new ehd must be the only one attached for it to format.