bluelittlegirl Said:
"Inactive email accounts keep reappearing: Thank you. Yes, I tried that, too. When I hit the '-' it tells me to go to internet accounts in System Preferences. I really do appreciate your suggestions, though. The overly enthusiastic but (hopefully only) poorly trained Apple service rep was extremely unhelpful. I miss the PowerBook era in so many ways. "
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You are welcome.
eMail Account Removal:
Restore or Reinstall Anew:
Does this occur on just this Mac? Or does it show up on all of your other devices? If just this Mac, then it would be a matter of (A.)restoration, or (B.)a new install. See the following...
A. Restoring the macOS:
Go Here: How to Reinstall macOS from macOS Recovery - Apple Support
Important: First, Back Up your Mac:
Prior to all of this, did you Create a Time Machine backup of your Mac? If so restore your Mac from it. If not, then take this as a learning experience, knowing to always create a backup of your Mac, prior to making any major changes to it (i.e. new install).
B. Reinstalling the macOS Anew:
See if this Site Helps: How to Reinstall the macOS Anew - No TMB Prior to Upgrade - User Tip. Format the hard drive with the applicable macOS, on step D.
In Depth:
Simply, it is a matter of:
- Erasing: and formatting your hard drive to APFS
- Installing: [the applicable macOS] via a USB Bootable Installer
- Restoring: info from a Time Machine Backup, using Migration Assistant