Symptoms

Internal users are receiving a server generated mail stating "Your message was deleted without being read" when they include a read receipt.

Cause

This issue is due to journal messages being disclaimed by Mail Utilities. Mail Utilities will abort and recreate internal mails in order to add a disclaimer and therefore the read receipts are aborted.

Resolution

There are two options to resolve this issue.

Option 1: Enable Envelope Journaling

If you are using Exclaimer Mail Utilities to journal messages, please open the Mail Utilities control panel and select the Enable Envelope Journaling on the Message Journaling section of the Setup page. (Please don't forget to save your changes) If you are using Exchange to journal messages, please refer to the following Microsoft Tech Net article that explains how to enable envelope journaling.
technet.microsoft.com/en-us/library/aa997541(EXCHG.65)

Option 2: Create a custom rule within Mail Utilities so journal messages are not disclaimed

Open the Mail Utilities control panel and click on Custom Rules from the menu on the left. Click on Add Rule at the bottom of the custom rules page. On the addressing tab of the Add Mail Rule window, please select Anyone internal for the sender. Please select Active Directory Users and Groups as the recipient and click on the Browse button within the recipient section. Once the "Select User, Contact or Group" window appears, please enter the object name for the journal mailbox, click Check Names and then click on OK. Once you are returned to the addressing tab of the Add Mail Rule window, please click on the Disclaimer tab. Please then select Don't add disclaimer from the drop down menu and click OK to close the Add Mail Rule window.
Please then ensure this rule is at the top of the list of custom rules. You may need to use the sender and recipient buttons at the bottom of the custom rules window to move the new rule to the top of the list.