To convert incoming HTML messages to plain text or Rich Text format

Outlook 2002 and Later Code Sample

Starting with Outlook 2002, you can call a VBA subroutine from a Rules Wizard rule using the "run a script" rule action. The procedure can be in either the built-in ThisOutlookSession module or any custom module and must include a MailItem or MeetingItem argument. This short example converts all incoming messages to plain text:

Sub ConvertHTMLToPlain(MyMail As MailItem) Dim strID As String Dim olNS As Outlook.NameSpace Dim olMail As Outlook.MailItem strID = MyMail.EntryID Set olNS = Application.GetNamespace("MAPI") Set olMail = olNS.GetItemFromID(strID) olMail.BodyFormat = olFormatPlain olMail.Save Set olMail = Nothing Set olNS = Nothing End Sub 

The other Outlook 2002 (or later) feature that makes this work is the BodyFormat property of the MailItem object, which allows you to set a message's format. Note that changing a message from HTML to plain text makes any embedded image attachments inaccessible from the user interface. They are still stored in the message, however, and can be accessed via code.

We have not done any testing to see how well the "run a script" rule holds up when the user receives hundreds of messages at one time.

NOTE: To avoid security prompts when accessing properties like Body and Recipients, you must use the technique above to get the item indirectly, through its EntryID property and the Namespace.GetItemFromID method. If you attempt to access MyMail.Body or MyMail.SenderName, for example (MyMail being the name of the parameter for the "run a script" rule procedure), you will get a security prompt.

WARNING: We have seen a couple of instances where a machine running Outlook 2002 with such a rule completely loses the VbaProject.otm file that contains all the Outlook VBA code. If you use "run a script" rules, be sure to back up VbaProject.otm regularly or export the individual modules.

This type of rule apparently should not be run by Exchange Server users working offline. See OL2002 Error Message The Message You Specified Could Not Be Found When You Synchronize.

Also see:

• OL2002 How to Create a Script for the Rules Wizard

Outlook 2000 CW Mode Code Sample

This VBA code sample for Outlook 2000 removes all HTML tags from new items arriving in the Inbox and saves them in RTF format. It needs to run in the built-in ThisOutlookSession module.

CAUTION: We recommend that you use this technique only if you are running Outlook 2000 in Corporate/Workgroup mode. If you use it in Internet Mail Only mode, your replies will also be in Rich Text format, which most Internet mail users (at least those not using Outlook) cannot read. They will get a mysterious Winmail.dat attachment, and any normal file attachments you send will be indecipherable.

Option Explicit Private WithEvents olInboxItems As Items Private Sub Application_Startup() Dim objNS As NameSpace Set objNS = Application.GetNamespace("MAPI") ' instantiate objects declared WithEvents Set olInboxItems = objNS.GetDefaultFolder(olFolderInbox).Items Set objNS = Nothing End Sub Private Sub olInboxItems_ItemAdd(ByVal Item As Object) On Error Resume Next If Item.HTMLBody <> vbNullString Then Item.Body = Item.Body Item.Save End If Set Item = Nothing End Sub  

This sample monitors only the Inbox folder. You could do much the same thing with other folders by adding code to do the following:

• Declare an Items collection object for each folder WithEvents
• Instantiate the Items collection object in the Application_Startup event handler
• Add an ItemAdd event handler for the Items collection object

If the incoming HTML-format message contains any background or embedded images, these appear as attachments in the RTF-format message.

Outlook 2000 IMO Mode Code Sample

Outlook MVP Neo offers this variation for Outlook 2000 running in Internet Mail Only mode, to remove the HTML content from the currently selected item using CDO. (Because CDO does not install automatically, you may need to rerun Outlook setup to add it).

If you want to run StripHTML automatically against all incoming items, then you'll need to use the same events as for the CW version above, but modify both the ItemAdd event handler and the StripHTML code to perform the removal on the Item that ItemAdd passes, rather than on the selected item.

Sub StripHTML() Dim olMessage As Outlook.MailItem Dim oMsg As MAPI.Message Dim oSession As MAPI.Session Dim strEntryID As String Dim colFields As MAPI.Fields Dim oField As MAPI.Field Const cdoPR_HTML_BODY = &H1013001E Set olMessage = _ Application.ActiveExplorer.Selection.Item(1) strEntryID = olMessage.EntryID olMessage.Close olDiscard Set olMessage = Nothing Set oSession = CreateObject("MAPI.Session") oSession.Logon "", "", False, False Set oMsg = oSession.GetMessage(strEntryID) Set colFields = oMsg.Fields Set oField = colFields.Item(cdoPR_HTML_BODY) oField.Delete Set oField = Nothing Set colFields = Nothing Call oMsg.Update(True, True) Set oMsg = Nothing oSession.Logoff Set oSession = Nothing End Sub  

Notes

In Outlook 2000, setting the Item.Body property automatically makes the format Rich Text (despite what the Help file says about it forcing the format to the user's default choice; that's an error in Help). Similarly, setting the Item.HTMLBody property would convert the item to HTML format automatically.

Starting with Outlook 2002, setting the Item.Body property really does convert the format to the user's default, and you can use the BodyFormat property to directly set the format of a message.

Tools

Attachment Options	Outlook COM add-in that sets the Read as Plain Text option.
Email Not HTML	POP mail download program that removes HTML content and embedded files (retained as one or more attachments) from a message before Outlook opens it. Also zips any attachments that aren't already zipped. Can be set to leave only "safe" HTML in the message.
NoHTML	Outlook COM add-in that works much like the ZapHTML code above, stripping HTML content as a user switches from one message to another.
PocketKnife Peek	Outlook  add-in to allow you to read the plain text version, HTML source, or Internet headers of any incoming message, all from one tabbed interface. Also includes a "Reply to Some" feature to generate a reply to selected recipients (fewer than "Reply to All"). Free for personal use.
Watch Your Back	Tool to strip HTML content and manage read receipts in incoming messages.

More Information

• OL2000: How to Create a Custom Rule Using Visual Basic for Applications -- Using VBA to monitor your Inbox
• To quarantine application file attachments with Microsoft Outlook 2000 VBA -- Another VBA code sample useful for isolating potentially dangerous files 
• Protecting Microsoft Outlook against Viruses
• HTML Mail Vulnerability Updates for Microsoft Outlook -- patches you need to avoid HTML mail-borne viruses
• Web Bug FAQ -- Information on how some mail senders use images in HTML messages to track who's reading the mail and when.