Beginning with Microsoft Office Outlook 2003, a new Personal Folders file (.pst) format was introduced that supports multilingual Unicode data and offers greater storage capacity for items and folders. You can determine whether your .pst files are in the new format or an earlier format.
- On the File menu, click Data File Management.
- On the Data Files tab, click the Personal Folders file (.pst) data file that you want to check, and then click Settings.
- View the Format field to see whether it contains the text Personal Folders File or Personal Folders File (97-2002).
Personal Folders File indicates the new format in Microsoft Office Outlook 2003 and Microsoft Office Outlook 2007 that supports multilingual Unicode data and offers greater storage capacity for items and folders. A file in the Personal Folders file format is not compatible with Microsoft Outlook 97-2002.
Personal Folders File (97-2002) indicates the .pst file format that is compatible with the versions of Outlook prior to Outlook 2003. Personal Folders file (97-2002) does not support Unicode and offers the same storage capacity for items and folders that was available in the previous versions of Outlook.