If you’re troubleshooting problems with Apple Mail, where it either is hanging or is displaying ghost messages in search results, try this troubleshooting technique…

  • Quit Mail
  • Navigate to ~/Library/Mail
  • Rename the file named “Envelope Index”, giving it a name something like “Envelope Index BU”
  • Relaunch Mail, and click Continue when asked if you want to import your messages
  • Wait for the process to complete
  • If the problem goes away, delete the renamed Envelope Index.