Headers

Each email you receive contains information about where the message came from and which computers it went through on its way to your mailbox. This information, contained in the message's headers, is usually masked from your view. When you display full headers, you're telling your email program to restore this information, which can be used to trace email back to its source.

When forwarding an unwanted or abusive email to postmasters for action, it's very important that you include all of the header information. A great number of spammers, for instance, will do all they can to blur the origin of their message, but they can't forge everything! So here's a guide to viewing full headers in a variety of popular mail clients.

Full Headers in Apple's Mail app under Mavericks:

  • To display all mail headers henceforth, go to:  Menubar => View => Message => All Headers
  • To show only the default headers henceforth, do the same but select Default Headers

Full Headers in Pine

  • From the Main Menu of Pine, press S for Setup, and then C for Configure.
  • Move down through the list of options under "feature-list" until you reach enable-full-header-cmd. (The feature-list options are arranged alphabetically.) Press X to make an X appear in the box next to that option.
  • Press E for Exit Config, and then Y for Yes when Pine asks if you wish to save the changes to your configuration.
  • Now, whenever you want to forward a given message with full headers, you can press H while viewing the message (so that all headers appear on your screen), and then forward as usual.

Full Headers in Elm

Unfortunately, although Elm will happily show full headers while viewing a message, it will not reproduce them when forwarding the mail. So the only method is a bit ugly and time-consuming...

  • While viewing the message you wish to forward, press h to show the full headers.
  • Press s to save the message to a file, and then type any filename you like (i.e. "foo" or "headers"). Elm will acknowledge the save, and then return you to the message index.
  • Compose whatever message you want to send to the postmaster. When you're at the spot where you wish to include the headers, insert the file "foo" (or "headers", or whatever you named it). If you're using Emacs, the command is CTRL-x i; in Pico, the command is CTRL-r; in vi, ESC:r foo. The file, consisting of the original message plus full headers, will be included in your mail.

Full Headers in Mutt

Older versions of Mutt handle headers beautifully: no muss, no fuss. Press h to view the headers, then f to forward the message. That's it!

In newer versions of Mutt your mime_forward variable must be unset. This is the default on most, but not all, systems. If forwarding a message does not put the full headers in the body, check that variable in your .muttrc.

Full Headers in Eudora

  • In Light versions 1.5.2 and below for the PC, 1.5.4 and below for the Mac, or Pro 2.0.2 and below, you can view the full headers but the program will not forward them--you will have to cut and paste the headers.
    • Select Special from the menu bar, and then Settings from the menu given.
    • Scroll down until you see Fonts & Display, and click on that item.
    • From the list of settings that appears on the right side of the dialogue box, click on the box next to Show all headers (even the ugly ones). An X should appear in the box.
    • Click on the OK button to save the settings.
    • Now, when you view a message, the full headers will be visible. To include them in mail you send out, highlight the lines with your mouse, and select Copy from the Edit menu; then, while composing your outgoing message, select Paste from the Edit menu.
  • For Eudora Light 1.5.4 for Windows, use the 1.5.2 instructions; the only difference is that instead of selecting "Settings" from the "Special" menu, you will need to select Options from the Tools menu.
  • For Eudora 3.0 and newer (Light or Pro), the process is much easier.
    • While viewing a message, you will see a button that says "Blah blah blah" (no, really!) in the upper left-hand corner of the message window. Click it to turn on full headers.
    • While the full headers are visible, just forward the message; they will be reproduced in the outgoing mail.

Full Headers in Pegasus

Pegasus is another mailer which will show you full headers, but not forward them, so you will need to use cut and paste.

  • While viewing a message, go to the Reader menu and select Show All Headers.
  • Highlight the headers with the mouse and select Copy from the Edit menu; then, while composing your outgoing message, select Paste from the Edit menu.

Full Headers in Netscape

  • In Netscape 3, you can forward full headers, but the recipient will not see them unless that person enables his mailer to show full headers. It doesn't behave as a bounced message, but rather as mail with two sets of headers. Very odd.
    • In Netscape Mail, go to the Options menu, the Show Headers item, and select All.
    • When you return to the message, you'll see all the headers. Just forward the mail (as an attachment, which is the default).
  • In Netscape Communicator, just go to the View menu, select Headers and then All, then forward the message as an attachment (which is the default). However, be aware that the recipient will have to view the attachment separately to see the headers; just looking at the message won't show them.

Full Headers in Thunderbird

  • Click on View->Headers->All
  • Under Preferences->General->Forward messages, select "Inline"
  • Forward the message of interest to someone (perhaps yourself). The forwarded original message will include the full headers in the text of the message.

To turn Full Headers off:

  • Click on View->Headers->Normal

Full Headers in Microsoft Outlook

  • Outlook Express will include the full headers if you forward the message as an attachment, but the recipient might not be able to read them. To send the full headers in plain text, just open the message, choose the "File" menu and "Properties", then click "Details".
    These headers can be copied with CTRL-C and pasted into a new message easily.=
  • Outlook 97
  1. Startup Outlook and double click the message to get it in its own window.
  2. Go to the "View" menu and select "Options."
  3. Right click in the box that contains the full headers and choose "Select All."
  4. Right click again in the same box and choose "Copy."
  5. Create a new message and paste the copied text into the body of the message.
  6. Fill in the address in the "To:" field as well as the subject, then send the message.
  • Outlook 98/2000/2002/2003
  1. Startup Outlook and double click the message to get it in its own window.
  2. Go to the "View" menu and select "Options."
  3. Right click in the "Internet Headers" box and choose "Select All."
  4. Right click again in the "Internet Headers" box and choose "Copy."
  5. Create a new message and paste the copied text into the body of the message.
  6. Fill in the address in the "To:" field as well as the subject, then send the message.

Full Headers in Hotmail

  • Once you are logged in, click on Options.
  • Click on Mail.
  • Click on Mail Display Settings.
  • Change the Message Headers section to Advanced.
  • Click OK.
  • Now when you read an e-mail, it should show you the full message headers.

Full Headers in Gmail / Google Mail

  • While viewing a message, click on More options.
  • Click on Show original.
  • This will display the headers for that message in a new window.