This is the update that caused the problem.
Update for Microsoft Office Outlook 2007 Junk Email Filter (KB2508979)
Download size: 3.2 MB
You may need to restart your computer for this update to take effect.
Update type: Important
This update provides the Junk E-mail Filter in Microsoft Office Outlook 2007 with a more current definition of which e-mail messages should be considered junk e-mail.
Description of the Office Outlook 2007 Junk Email Filter update: March 8, 2011
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