If you're using Outlook 365 and need to access or back up your emails, you might be wondering how to convert an OST file to PST. Many Outlook users get stuck when trying to open or move data from an OST file, especially when something goes wrong with their account or device.

In this guide, we’ll explain everything in simple words so that even someone with little technical knowledge can understand how to handle this task.

We’ll cover:

• What is an OST file?

• What is a PST file?

• Why you may need to convert OST to PST in Outlook 365

• How to do it manually

• When to use an OST File Converter

• The best OST to PST Converter Software

• Step-by-step instructions

What Is an OST File?

An OST (Offline Storage Table) file is a copy of your mailbox data that is stored locally on your computer by Microsoft Outlook. It allows you to access emails, calendar items, and other data even when you're offline.

Whenever you reconnect to the internet, Outlook syncs changes between the OST file and the server.

What Is a PST File?

A PST (Personal Storage Table) file is a file format used by Outlook to store emails and other data on your local drive. Unlike an OST file, a PST file is not tied to a specific Outlook profile or email account, making it easier to move or back up.