Disable previews in Mac Mail

    Disable Inline Attachment Previews (Using Terminal)

  1. Quit the Mail app completely.
  2. Open the Terminal app (in Applications > Utilities).
  3. Type the following command and press Enter:
  4. defaults write com.apple.mail DisableInlineAttachmentViewing -bool yes.
  5. Restart Mail to see the change; attachments will now appear as icons.