Undeliverable: Delivery Status Notification (Failure) We get the following message if the recipients mail box is full The following recipient(s) could not be reached: mailtest on 5/7/2008 5:17 PM This message is larger than the current system limit or the recipient's mailbox is full. Create a shorter message body or remove attachments and try sending it again. We would wish to replace the above Undeliverable message with: " Thanks for your message, users mail is unavailable to take you message if this mail is official kindly resend to abc@xxx.zz" Our environment : MS Exchange 2003 in cluster mode. Which file / registry entry in MS Exchange should we edit to modify the message. Thanks & Regards, Maqsood