If you send an email entirely within Exchange and it never leaves the server
there will not be any PR_TRANSPORT_MESSAGE_HEADER in the email Exchange does
not add those headers for internal emails.

If you send an email over the Internet the received email will have the
PR_TRANSPORT_MESSAGE_HEADER property. The sent item in the Sent Items folder
will never have that property, so I have no idea what you're talking about.
Check it yourself with a MAPI viewer such as OutlookSpy. There are no
headers in the sent item, period.

In a case where there is no property like that obviously there are no
headers, so how can you read the headers? It's impossible.

If you are adding headers to outgoing items using the special named MAPI
property trick then in internal only emails that stay within Exchange there
still won't be any PR_TRANSPORT_MESSAGE_HEADER property on the item but the
MAPI property you added will be there and can be read as a MAPI property.

--
Ken Slovak
[MVP - Outlook]
http://www.slovaktech.com
Author: Professional Programming Outlook 2007.
Reminder Manager, Extended Reminders, Attachment Options.
http://www.slovaktech.com/products.htm


"Ashish" wrote in message
...
If i login to exchange user, create a new mail and send to same user then
mail comes in its Inbox and SentItems folder. And both mails have
PR_TRANSPORT_MESSAGE_HEADERS property. I need mail header b'se i write my
own data in mail header(urn:schemas:mailheader:mytag)
In outlook addin i need to get mail header b'se i want to get mytag which
i wrote in mail.

For below specific case when send a mail using web page, mail dont contain
PR_TRANSPORT_MESSAGE_HEADERS. So my question is
"Is there any possiblity to get mail header in outlook addin if above
property is not present"