Microsoft Outlook categorizes Outlook Data Files into two types: PST and OST files. PST files contain data stored in your personal folders, whereas OST files contain data downloaded off your ...

What causes This data file is associated with a mail account OST file on Outlook? It’s a very unusual error, and there is no specific reason why it may occur.

What's the max size of an OST file? I ran into this after upgrading someone from Outlook XP to Outlook 2003 (same Exch 2003 server), where email stopped working because there seemed to be a max ...