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
Open OWA and select Options (shown in the lower left corner of the image that follows)
Scroll the Options in the right pane and identify the Privacy and Junk E-mail Prevention section.
Thick the Filter Junk E-mail checkbox.
Click on Save and Close button to save changes.