The Seagate backup drive is installed correctly as the icon is displayed on the desk top and is listed in Disk Utility.
However, Time Machine will not recognize that specific back up drive.
Options does not allow "Add a backup drive" for this Seagate hardware.
iMac
Per chance is this external drive formatted for NTFS? If so, Time Machine will not be able to back up to it, and it will need to be re-formatted in order to work properly.
Ref: Backup disks you can use with Time Machine - Apple Support
Where did this "you are welcome and thank you too" come from?
I just opened Mail for the first time. I am sorry, but your suggestion makes no sense as it erases all of the data on that external drive. There's a lot of data on those drives that I desire to retain.
Would suggest Reformatting the Drive on the computer it is intended to be used.
By virtue of the User ( you ) marking the suggestion as Solved ( Green Badge ) that denotes the user who made that suggestion ( P. Phillips - me ) Solved the Original Owner of this Question ( you ) as Solving your question.
As a token of appreciation and acknowledgement of your marking the suggestion as Solved I generally offer a You are Welcome and Thank you too
You are welcome and thank you too 🇨🇦
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Thanks but none of those basic suggestions apply. It has always connected properly until now. This is a totally new issue to Time Machine that I have been using for more than 20 years.
Time Machine Does not recognize Seagate backup drive for backup
