Why delivery receipt size is same than sent email size or even larger?


New Member
Outlook version
Outlook 2010 32 bit
Email Account
Exchange Server 2013
No matter which Outlook version is used, I am wondering the fact why Delivery receipt size is the same than the sent email specific or little larger.

Example: You send a 10mb email to XX and Delivery receipt is 10 or 11 mb sized. When you view the delivery receipt content, it just informed the email being delivered or not. From File -> properties you can see the headers, but the amount of internet headers is surely not 10 mb sized.

Is the actual sent email somehow hidden included on delivery receipt? If that is the case, how to get it visible?

I know the differencies of read and delivery receipt but couldn't find any KB or other about the size of delivery receipt how it is generated and so.

Diane Poremsky

Senior Member
Outlook version
Outlook 2016 32 bit
Email Account
Office 365 Exchange
This is the message I got from my office 365 account:
Delivery to these recipients or groups is complete, but no delivery notification was sent by the destination server:
the delivery message was 42KB, the original message was 3MB.

when i sent it to another exchange account and got back this:
Your message has been delivered to the following recipients:
the delivery receipt was 77KB.

Both are bigger than (I think) they should be, but clearly don't have the 3MB file attached.

if you send to more than one person and use conversation grouping, the size field shows the total size of all receipts in that thread. (But it would take a heck of a lot of get 10MB worth, even at 77KB per message.)