QSearchFolders creates search folders and manage existing search folders in all versions of MS Outlook and in each place in an Outlook tree. It makes the automatic scanning of Outlook folder such as email and contacts, tasks, calendars possible.
One of the new features of Outlook 2003 are search folders, once created the for example show all your unread messages in all folders or messages matching any criteria. Search folders automatically search the specified folders in the background and update themselves if the data changes.
Search folders are a part of MAPI, the data base engine on which Outlook is based and are part of the definition since the first version of MAPI which was introduced about 1995. In other words, all versions of Outlook are able to display search folders, missing is only a user interface which allows creating them. In fact, all versions of Outlook are using search folders in the extended search dialog.