View Full Header of an Email Message

Email Headers contain all the information about where an email has been; how many computers it has been routed through; and more.

This information is easy to access but not often (cybersecurity outfits will use it along w/ other methods to track down spam and spammers). We can use email Header info to see if something like a web proxy or IP distorter is used, or just to see if the IP address listed matches that of it’s purported sender.

Google Mail (Gmail):

1) Open the email you want to examine.

2) Click the “down arrow” next to the “Reply” hyperlink

Note: There is no down arrow w/Gmail using Mac OS X and Safari 3.0.4.)

3) Select “Show Original.” A new window opens with the full header as plain text.

Select "Show original".

– Yahoo! Mail: select “View Full Headers”, or “View Headers.”

– Windows Live Hotmail (this does not work w/ Safari or Mac OS…):

Select “View Source”. A window opens displaying the full header as well as the HTML source of the email message.

Desktop Email Clients:

Typically the option for viewing the full email header w/ desktop email clients like Outlook and Thunderbird are found in their drop-down menus.