The information on this page applies to obsolete versions of Outlook.
If you have Microsoft Outlook 98 or Outlook 2000, Microsoft provides a feature called Net Folders that transfers information among a group of people with special e-mail messages; this feature is more stable in Outlook 2000, but still not 100% reliable.
The Net Folders feature was added in Outlook 98 to meet the need for some kind of sharing in a non-Exchange Server environment. It replicates information via special e-mail message and, therefore, requires that the people participating the the sharing all be able to communication via e-mail. Unfortunately, Net Folders is nowhere near 100% reliable. Users may experience data that doesn't replicate, shares that stop working completely and other problems. See Sharing with Net Folders.
However, this feature doesn't exist at all in Outlook 2002 and later versions and you'll need to change to a new method of sharing when you upgrade your version of Outlook.