Previous versions of OWA didn't let you look at mail headers. In Exchange 2007, you can. Open a message in OWA by double-clicking on it or hitting Enter, then click on the "Message Details" icon.
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Updated Jul 01, 2019
Version 2.0
Blog Post
Viewing message headers is one of the most important and essential things of emails. About 1 one 20-30 messges I receive are messages where I want to see the headers.
What about the user calling the help desk and they need to see the headers?
Also it is strange that (in current Exchange and Outlook 2003) I can only see the headers of mails in my inbox, not in attachements from forwarded mails: If someone attaches an EML-file to an message or forwards a complete message with thunderbird, Outlook goes in, messes everything up and is not able to show me the embedded headers.
HEADERS ARE A VITAL PART OF INTERNET MESSAGES AND MAY NEVER BE LOST!
What about the user calling the help desk and they need to see the headers?
Also it is strange that (in current Exchange and Outlook 2003) I can only see the headers of mails in my inbox, not in attachements from forwarded mails: If someone attaches an EML-file to an message or forwards a complete message with thunderbird, Outlook goes in, messes everything up and is not able to show me the embedded headers.
HEADERS ARE A VITAL PART OF INTERNET MESSAGES AND MAY NEVER BE LOST!