Consider the following scenario:
- You use Microsoft Office Outlook 2007 or Microsoft Outlook 2010 to receive email messages in Windows Vista, in Windows Server 2008, in Windows 7, or in Windows Server 2008 R2.
- You receive a compressed S/MIME email message that is created by a third-party Outlook add-in.
- The third-party Outlook add-in is not installed on your computer.
- You try to open the email message.
In this scenario, Outlook crashes.