I recently found a bug with Outlook for Mac 2011. I submitted it to MSFT since the company I work at has a premier T3 contract, but they declined it since it is being fixed in the next version.
Outlook for Mac 2011: Overview: Within Exchange 2007 / 2010 / 2013 if a sender sends an email internally, it should be inherently trusted as the SMTP domain is part of the Accepted domain. For example, lets say your accepted domain is contoso.com. Your email is [email protected], and you add (within Outlook) [email protected] to your Junk email blocked senders list then two things will occur: 1) The entry (both safe and blocked senders) is synced to the Exchange 2010 server, stored locally on the clients mailbox (you can view safe / blocked senders listings via Get-MailboxJunkEmailConfiguration in Exchange 2010 / 2013) 2) When [email protected] emails [email protected], although it is added to the Junk email blocked senders list it will still go into the Inbox then sorted through the rules. Why? Because this is an inherit trusted domain, and the SCL mapi value (I will get into that below) is automatically set to -1 Issue: Outlook for Mac does not like to follow the same logic as displayed above. What occurs here is a tad bit different: 1) Outlook for Mac does not sync the blocked / safe senders list at all to Exchange. Ever. 2) Outlook for Mac will disregard the accepted domain, and simply filter emails based off the blocked / safe senders listing. Meaning, if I add [email protected] on accident and he emails me, his emails will automatically go into the junk email folder. 3) If the Outlook for Mac client is off, and then is turned on it will actually scan the mailbox for emails that are within the junk email blocked senders listing and then move them off into the junk email folder. Resolution: Make sure your clients that are using Outlook for Mac 2011 do NOT add anyone internally to there blocked senders list. The other thing I wanted to note is how the SCL values are actually handled within Outlook. The SCL value you see on your msg headers is the one for Exchange, and is not the same thing the Junk email filter utilizes. When Outlook pulls an email down, and RPC Encryption is enabled (see my other commentary below on another "known issue" with Outlook 2007 / 2010 / 2013) the junk email filter reviews the MAPI property PR_CONTENT_FILTER_SCL instead of the actually SCL on the header. Sometimes this is different for whatever reason (I honestly do not know why) so keep that in mind if you are dealing with a similar issue, but with Outlook 2007-2013. Now to my Outlook 2007 / 2010 / 2013 "known issue": Overview: If the check-box "Encrypt data between Microsoft Outlook and Microsoft Exchange" is not checked off, and you are using Exchange 2007 / 2010 / 2013 then the Junk email filter will not work within Outlook. This box is found under - Change Account > More Settings > Security > (Encryption section) Resolution: Check off the box that states "Encrypt data between Microsoft Outlook and Microsoft Exchange" Hopes this helps out with any Outlook junk email issues you might encounter.
