You can remove the "Bad Email" indicator from a users record through People Finder.

To remove the Bad Email indicator through People Finder:
  1. Navigate to Core.
  2. Select People Finder.
  3. Search/select your user.
  4. Click the Contact Card tab.
  5. To the right of the Digital section, click the yellow pencil/Edit icon.
  6. Un-check the "Bad Email" indicator.
  7. Save.