Outlook Has E-Mail Junk Problem on Exchange 2013

Microsoft's Outlook e-mail program has been sending regular messages into the junk bin, Microsoft noted this week.

The problem is specific to using Outlook with Exchange Server 2013 or Office 365's Exchange Online service. The glitch is described in this Knowledge Base article, where Microsoft promises that is looking into the problem with more information to come. In the meantime, a few workarounds can be found in a blog post today by the Exchange team.

The problem stems from Microsoft taking a different approach with how junk mail gets filtered. Outlook now passes all mail through its junk mail filter, weighing which should be deemed spam and which is trusted. In the past, Exchange used a Messaging Application Programming Interface (MAPI) property called "PR_CONTENT_SCL" that indicated a "spam confidence level" for the message. Messages that were marked SCL -1 got through, but now Outlook just ignores the SCL property altogether, according to Microsoft's announcement.

The problem affects trusted e-mail from external domains, as well as internal traffic. While the company isn't offering a fix at present, there are three workarounds to try, according to the Exchange team.

The most drastic workaround approach is to simply disable Outlook's junk e-mail filter or lower the level of protection under the Junk E-mail Options tab in Outlook. Another approach is to add the wanted senders to Outlook's safe sender list, but both the name and domain of each e-mail address have to be specified in that list as clearing the domain alone doesn't work. The last option Microsoft describes is to "add a mail-enabled contact in Active Directory for the affected internal address."

Microsoft's Knowledge Base article currently suggests that the problem with wanted mail going into the junk mail folder could be due to an encryption problem between Outlook and Exchange Server. The Exchange team blog post doesn't mention that possibility at all, though. The Knowledge Base article offers a workaround to enable "RPC encryption between Outlook and Exchange."

The Exchange and Outlook teams have sometimes run into snags. For instance, a public folder copy problem in Outlook popped up last year because Microsoft's engineering teams removed some Outlook code that initially had been thought to be obsolete after an improvement was made to Exchange 2010 Service Pack 1.

About the Author

Kurt Mackie is senior news producer for the 1105 Enterprise Computing Group.


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