Last reviewed on August 23, 2012   —  5 Comments

Applies to Microsoft Outlook 2013, Outlook 2010, Outlook 2007, Outlook 2003

View message source codeBeginning with Outlook 2003 you can view the header and message source code source together in the options dialog, provided you edit a registry key.

This works on mail downloaded from Internet mail transports only, meaning it works with POP3 and IMAP accounts only (and EAS in Outlook 2013), not Exchange server mailboxes or Outlook Connector accounts.

Header and Source sample

To learn how to open the Message options dialog so you can view the Internet Headers, see How to View Internet Headers

Note that setting this registry value will result in larger messages stored in your data file. For this reason, you may want to use this key only when you need to troubleshoot issues. If you delete the key (or change the value to 0), the source code will not be removed from messages already downloaded.

Set the SaveAllMIMENotJustHeaders registry value

Open the registry editor and navigate to the correct key for your version of Outlook, then right click on Mail in the right pane and choose new DWORD, naming it SaveAllMIMENotJustHeaders. Set a value of 1.

Outlook 2013

Parameter: SaveAllMIMENotJustHeaders
Value: 1

Outlook 2010

Parameter: SaveAllMIMENotJustHeaders
Value: 1

Outlook 2007

Parameter: SaveAllMIMENotJustHeaders
Value: 1

Outlook 2003

Parameter: SaveAllMIMENotJustHeaders
Value: 1

After editing the registry, restart Outlook then view the message headers of messages that were downloaded after you restarted Outlook.

Do It For Me

Download the correct file for your version of Outlook, then double click to add it to the registry.

Outlook 2013 Outlook 2010 Outlook 2007 Outlook 2003

Remember: This works only with POP3, IMAP, and EAS accounts and only for messages not yet downloaded. To view the source for POP3 accounts where messages are left on the server, create a second account in Outlook and re-download the messages.


    • Diane Poremsky says

      If the mailbox can be accessed using POP3 or IMAP, you can use the method on this page - it's not that it doesn't work with Exchange mailboxes, but that it only works when you use the POP3 or IMAP protocol.

  1. David Karasiewicz says

    HI Diane,

    Thank you for post. It seems that I've missed something because I do not see the ...\options\mail. Once I get to ...\options there are four other folders: Calendar, General, MSHTML and Spelling. Has there been one or more changes since your post? I'm using IMAP protocol.


    • Diane Poremsky says

      If the folder does not exist, create it. They are only added ot the registry if you make a change to options that writes to that key. If you change some settings on the Mail options page, it should add the Mail key for you.

  2. David Karasiewicz says

    Many Thanks,
    This works. Okay they are call "Keys", not folders as I called them.. :)
    Also adding the properties (Message Options) to the tool bar works nice for my needs too.

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