Below are ways to view the advanced headers of email messages in some common email programs. This is useful for identifying spam, and illegitimate email account use within a company.
With the message in its own window, click the message tab, look at the options block, and click the small button with the arrow on it (bottom right corner). This will open the message options. The Internet Headers will be displayed at the bottom of the box.
If the message isn’t open in its own window, right-click the message and select Message Options.
Outlook 98, 2000, 2003
With the message open, click on View -> Options. Near the bottom you will see a section called “Internet Headers.” Select the options accordingly.
Go to Options -> Preferences -> Under Headers click Advanced Headers
In the menu, go to View -> Headers and select All.
With the message open, double-click the “blah blah” icon (left of subject field) to reveal the advanced headers.
Highlight the message and go to File -> Properties -> Detail Tab -> OK. The properties box will then display the fill headers. Press Message Source.