In Exchange 2003 the Junk Email folder is a key anti-SPAM protection weapon. Acting as the SPAM repository it enables the Inbox to remain clean. Starting from Outlook 2003 you will find the folder ready, waiting to welcome incoming junk. It has its nice little eloquent icon, filling you with confidence that SPAM has its days counted.

In reality the folder in itself is no wiser than the others. To make the magic happen there is a lot going on. Somewhere down the line an anti-SPAM engine is analyzing the emails. It has to face the latest tricks invented to disguise junk as legitimate email. Finally given that everything is correctly configured emails will find themselves lending into the Inbox or Junk based on this filtering.

The mechanics behind this operation is in fact quite tricky. Being an Exchange professional for many years I like to keep an eye on the public newsgroups for the Exchange community. It is indeed becoming very common to see administrators complaining that "the Junk Email folder is not working". This article focuses on giving a better understanding of this folder as a basis for troubleshooting problems related to its enablement/disablement.

What filters are you using?

This question might sound trivial, but seems to be a very key pitfall. On one hand you have people believing that the Junk Email folder contains some magic that would automatically reach out and trap SPAM. I hope the article introduction already cleared this point.

Sometimes you also find some who are simply unaware of all the filtering technology running on their network. In my previous article, Bringing Together the Exchange Anti-SPAM Cocktail I discussed four independent SPAM filtering layers provided by Exchange and Outlook. With third party anti-SPAM solutions more filtering technology is introduced.

Before reading further, take the time to read my previous article. Make yourself a picture of all filtering stages. Most importantly make sure not to exclude third party filters from the picture. Indeed third party solutions could be overriding the logic of how emails are deposited to Junk altogether. Covering third party solutions is certainly beyond the scope here. Check the application vendor documentation for any related information.

Is Junk Email Enabled?

Given that all filtering layers are functioning correctly, there is still a final stumbling block. The Junk Email folder must be enabled. This enablement is per mailbox. Thus each recipient can choose to enable/disable it independently.

To complicate matters further, there exist two folder enablement mechanisms. You can enable it either through Outlook 2003 or through Outlook Web Access. It is a common perception that OWA is just the web based version of Outlook. To a large extent this is true, but not for Junk Email enablement!! This point is really important and we will get back to it in a moment. Before let's see how Junk Email is enabled through these interfaces.

Enabling Junk Email through OWA

1. Open OWA and select Options (shown in the lower left corner of the image that follows)

   

2. Scroll the Options in the right pane and identify the Privacy and Junk E-mail Prevention section.

3. Thick the Filter Junk E-mail checkbox.

4. Click on Save and Close button to save changes.

Enabling Junk Email through Outlook 2003

1. Open Outlook and select Tools | Options

2. On the Preferences property sheet click on the Junk E-mail button.

   

3. In the Options property sheet of the dialog that opens you can set the level of junk email protection to Low, High or Safe Lists Only.

   

4. Click on OK twice to close the Junk E-mail Options and Options dialogs and save changes.

Differences between Junk Email Enablement Mechanisms

A very typical problem is to have the Junk Email folder apparently disabled but still receiving filtered emails. Conversely you can find cases where despite being enabled, SPAM goes to the Inbox instead of the Junk folder. This is what happens when the wrong enablement mechanism is used.

The fact is that the Outlook and OWA interfaces enable different functionality. To understand this point you must first have a clear understanding of the four anti-SPAM protection layers provided by Exchange and Outlook. If you still haven't read my article Bringing Together the Exchange Anti-SPAM Cocktail then you should do it now.

Outlook 2003 enables the client side anti-SPAM filter. This is the anti-SPAM technology available to all Outlook 2003 users independently of whether or not they are using Exchange 2003.

OWA enables Junk Email folder delivery for the server side anti-SPAM layers. This filtering capability is available to Exchange 2003 users independently of the Outlook client version in use. OWA enables filtering to Junk Email folder for the Intelligent Message Filter but Outlook 2003 does not. Actually this is not 100% true and I will get back to this in a moment.

So what this means is that if you are using the Intelligent Message Filter, maybe with extensions such as IMF Tune, then OWA is the correct enablement interface. On the other hand, if you are relying on client side filtering, then Outlook 2003 enablement is the correct way forward.

Finally there is also an area of overlap! Both Outlook 2003 and Exchange support Safe Senders, Safe Recipients and Blocked Senders lists. The lists themselves are shared. Thus any changes you do at Outlook will appear at OWA and vice-versa. Still under the hood these are processed at two different filtering stages. This is good as it gives a consistent experience at least as far as these lists are concerned. Still it does help to reinforce the miss-conception that Junk Email enablement at OWA is the same as that as Outlook 2003.

Outlook 2003 Default Settings

A client of mine is running Exchange 2003 with the Exchange Intelligent Message Filter and Outlook 2003. He is happy with IMF and doesn't care about client side filtering. Hence he never applies the Outlook filter updates. No one ever uses OWA so it is certain that no one ever enabled Junk Email through it. Nevertheless the system works like a charm!

Outlook 2003 on connecting first time to a mailbox enables Junk Email for both client and server filtering. This is really the only case where Outlook manipulates the setting available through OWA (as far as I know).

In this manner Outlook 2003 gets Junk Email enablement by default also for the Exchange server side filtering. Still when it comes to disabling it one has to go through the OWA interface! Disabling it through Outlook will have no effect if IMF is in use.

Managing Junk Email Enablement

This really brings us to another question. With per mailbox enablement there is clearly an administrative problem. We need something for the administrator to centrally enable/disable Junk Email. I will be discussing this point in another article, so stay tuned to ExchangeInbox.com through our RSS feed

References

Bringing Together the Exchange Anti-SPAM Cocktail