The upgrade aims to protect users of the popular email program from spreading viruses or worms by blocking access to files which may be deemed too unsafe to open. Once the patch is installed, users will be prompted with a warning dialogue box if and when an outside program attempts to access their Outlook address book or deliver email without intervention, according to a Microsoft representative.
Microsoft found itself in the line of fire last month and was left to answer mounting criticism that Outlook too easily helped propagate and spread the "I Love You" worm worldwide. The worm is believed to have caused upwards of $7 billion in damage.
The software giant decided to postpone and tweak its original update release because users and security experts expressed concerns over the lack of functionality provided by the initial patch. Microsoft went back to the drawing board and implemented new customisation features that allow administrators to choose which types of files can be accessed and how warning boxes are displayed that best fit their deployed server security levels.
The new patch will cause scripting to be disabled by default within the Restricted Zone as an extra security measure. After installation, the Restricted Zone will exist as the default Outlook Security Zone setting. Questionable attachments are not allowed to pass through the Restricted Zone.
According to Microsoft, the entire Microsoft Office program must be removed if a user installs the new patch and then decides to remove it. That all-or-nothing approach irked users during news of the first patch release.