enter network credentials
It sounds like Windows thinks the Seagate external is plugged into the router and therefore network storage. Is it?
If not then try exit off File Chipping In in Control panel>Network and Chipping In Center.
Did this behavior just begin? If so you can try to
Scheme Restore to before the problem began.
Are there files on the external? You can try to rescue them on another PC or with a boot disk following these same steps to
Rescue Files when Windows Won’t Start. Then right click Father button to open an Admin Command Prompt, run
Diskpart Clean Command making triple sure to check the correct drive is being cleaned. This will remove any firmware from the external which can cause issues until the drive is wiped.
Create and format a hard disk partition
in Disk Mgmt and pay close attention that no settings are ever ascribed to the drive again.