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Allow a few e-mails HTTP access

HTML formatted e-mails

HTML formatted e-mails are not really e-mails (according to some people, though I quite like them and prefer to recieve HTML formatted e-mails especially if they are newspapers or newsletters). There more like web pages then e-mails, this can be quite useful if you subscribe to a newspapers daily e-mail as you get to see pictures as well as text and just like in a web page an HTML formatted e-mail can use well designed typography making long documents much more easier to read then the same e-mail in plain text could ever be. Also like a web page scripting can be embedded in the HTML code as can music and movies.

While this can be great if you planned to receive an HTML formatted e-mail it's not great when used by spammers as they can embed web bugs in the e-mail, run malicious scripts and so on. This is why a lot of people don't like HTML formatted e-mails and of course HTML e-mails use up your bandwidth whenever you view them as they will try and download images, sounds, external stylesheets and scripting etc. to display in the e-mail using HTTP (port 80).

So is there away to allow only certain e-mails HTTP access while denying HTTP access to all other e-mails?

Yes there is. You can create additional rules for your e-mail client(s) that will allow you to control which HTML formatted e-mails can use HTTP to download their content.

Creating the required rules

For this example I will assume you want e-mails from the BBC to be allowed HTTP access, but the idea behind it can be used to create rules for any other e-mail that you want to be able to use HTTP.

The first thing to do is to turn of any 'Allow it' HTTP rule that you have all ready created (either on your own or as part of your e-mail clients preset). Assuming you have created rules (using the preset) for Outlook Express, turn of (un-check) the rule Outlook Express HTTP connection.

Then make sure you are in Rules Wizard mode.

Now open the e-mail you want to have HTTP access (in this case from the BBC) and you will see a popup window appear from Outpost asking if you want to allow Outlook Express HTTP access to news.bbc.co.uk. In the popup windows combo box you will see Outpost has already selected the 'Outlook Express preset'. Don't click 'OK' now, first select 'Other...' in the combo box and then click on the button 'OK':

When the Rules window appears toggle the 'Allow it' Action check box and change the name of the rule to Outlook Express allow e-mails from the BBC HTTP access (if you want to you can call it something else):

The only difference between this rule and the preset HTTP rule that you turned off is that an additional Action has been selected, in this case a 'Remote Host' (news.bbc.co.uk). Now whenever you try an read the BBC's daily News e-mail Outpost will allow it to download any images, stylesheets, scripts etc. that the e-mail needs, allowing you to view the complete e-mail:

Denying all other e-mails HTTP access

The next thing to to do is put in place a 'Deny it' rule below the newly created 'Allow it' rule for BBC News e-mails. We all ready have the rule created (remember the rule you turned off), all you need to do is turn it on again and change it's action from 'Allow it' to 'Deny it':

Then move it below any 'Allow it' HTTP rules you may have. In this example move the rule below the rule allowing HTTP access for BBC News e-mails:

You may also want to change the name to show that it is denying HTTP rather then allowing as I have done in the above picture.

This will work for any e-mails, all that will be different is the 'Remote Host' that you will need to specify. Also remember that although you have allowed e-mail HTTP access, whether that e-mail can actually use active elements is decided by the Active Content plugin which has options for specifying what e-mails can and can't do. Also remember to only create rules for domains you actually need to contact, CNN e-mails for example, only need access to www.cnn.com but you will see in you logs if you make a rule for CNN e-mails that your e-mail client tries to access several sites like www.tm0.com and so on. These are where adverts in the e-mail are coming from so you don't want to allow this. If your not sure about what domains and e-mail should be allowed to contact block them first and if you find part of the e-mail is not being displayed it is easy enough to allow access to the domains you have blocked.

One more thing to note is that using these rules won't stop e-mail that just uses HTML for layout from displaying (like an email made a Hotmail using Hotmail's 'stationary') as these kinds of e-mails come with the images embedded in the e-mail.

You can take this even further when it comes to Hotmail, by following these rules.

Outpost and the Outpost logo are ©Agnitum Software

This is an unofficial guide, the information expressed here may differ from Agnitum's. There is a support forum (no longer run by Agnitum, but by users) if you need more help this is a good place to start. Where information here conflicts with what Agnitum have told you always go with the information given to you by Agnitum.

Guide/site and images ©Stephen Cox