What data file types does Outlook support? While working with Outlook, you will encounter two data file types: OST and PST. OST (Offline Storage Table) file types allow you to work offline.

Learn how to sort folders alphabetically in Outlook 365 or MS Outlook Classic and Outlook New (Steps valid for Outlook web).

Personal Storage Table or PST is a popular and most commonly used mailbox data file format for storing, backing up, and migrating mail items to and from Microsoft Outlook. However, Outlook data ...

If you receive an error 0x8000ffff in Outlook when adding a data file, add the Outlook data file using Account Settings to fix the issue.