Do not allow e-mail postmark functionality

By default, e-mail messages in Outlook can be "postmarked." E-mail postmarking is a feature that helps junk e-mail filtering software to distinguish regular e-mail from junk e-mail. Enable this setting to prevent e-mail postmark creation and processing in Outlook.

Supported on: At least Windows Vista

Registry HiveHKEY_CURRENT_USER
Registry PathSoftware\Policies\Microsoft\Office\12.0\Outlook\Options\Mail
Value NameDisablePostmarkingOnSend
Value TypeREG_DWORD
Enabled Value1
Disabled Value0

outlk12.admx

Administrative Templates (Computers)

Administrative Templates (Users)