Users do not need Edit or Add rights for gifts to be able to process Donor Acknowledgement Letters and Receipts, or to be able to mark the gifts as Acknowledged or Receipted via Mail.
  1. The user will need Security Rights to Mail> Donor Acknowledgement Letters and/or Mail> Receipts to successfully perform the task. 
Note: Users do need edit rights to run the letter directly from the gift record or mark the gift acknowledged or receipted directly on the gift record.