Gone are the days when we all used POP3 for emails. If you are using Outlook 2000/2003/2007 or Thunderbird 2, then you can grab the SpamBayes add-in which is probably the best free intelligent spam filtering tool out there. More and more users now are migrating to IMAP which is robust in both Outlook 2010 and Thunderbird 3.
If you are using Gmail(with IMAP enabled) in Outlook 2010 and it fails to filter a junk/spam email, then the email will land straight in your inbox. By default Automatic Filtering is turned off in Outlook 2010(see screenshot below).
To experiment it, I emailed myself about ‘Viagra’ pills which consists of 80% of all spam emails. It was not filtered by Gmail and landed straight in my Outlook inbox.
Note: I used quite some strong words in the email title and description to test out the spam filter. Screenshot NSFW(Not Safe For Work)
Outlook 2010 does however have options to choose the level of junk email protection you want. I select Low level protection and add the email to blocked senders list. Now the email first appears in my inbox and moves to junk email folder only when it is opened. That’s weird.
In the third and final experiment, I remove the email from blocked senders list and makes sure Low level protection is selected. This time the email arrives in my inbox and does not move to junk folder until it is opened. Huh? What’s the point of junk email filtering if Outlook cannot move the email automatically?
Since Outlook 2010 is in beta, we cannot say much. But what we have learned is that the junk email filtering engine does not start unless the email is not opened.
I believe it has more to do with IMAP rather than Outlook itself, with IMAP the email in your inbox is showed immediately and upon clicking if Outlook determines the email to be unsafe it is moved to Junk folder. Perhaps it is intentional but we could be wrong.
Update: You will definitely be interested in a 3rd part spam filter add-in for Outlook 2010 called AntySpam, do check it out!