I recently upgraded my system and installed the latest version of Microsoft Outlook. I still have my old Outlook data file that contains all my important contacts from an older Outlook version. However, when I try to open or import the file, my contacts either do not appear correctly or Outlook does not recognize the file format at all. I searched online and found that many people recommend using a converter tool, but I am confused about why it is necessary. Is there any way in Outlook to access old Outlook contacts directly, or is a converter tool the only reliable option?