OST vs PST: What’s the Difference between OST and PST files in Windows Outlook?

OST vs PST

Every software program dealing with data saves the data in some form of files inside the users’ database directory. Same with the email client like Outlook. When you use Windows Outlook, your emails, contacts, calendar data, and other items are stored in files inside the profile database directory.

OST vs PST – What’s the Difference between OST and PST

Windows Outlook primarily uses PST to store data. It’s short for Personal Storage Table and is a proprietary file format from Microsoft. But with Outlook, there’s another file, which is just a small variation of PST, called OST.

Microsoft Outlook Archive PST file

It’s short for Offline storage table and is used in the same way as PST except for offline mode. It’s typically used with Microsoft Exchange server account and is basically just an offline copy of your data and does not need to be backed up to PST. It allows users to work without internet connection and any changes made in an offline mode is synced to the servers when the connection is restored.

PST is also used to archive data locally on computer. OST cannot be used that way. You can save your emails and other items to an archived PST file for future use. It’s not limited by the space allowed by your email providers on the servers, so you can create PST file up to any size and that can help you reduce space on servers.

Microsoft Outlook OST file

OST, on the other hand, allows you to make changes like adding or deleting a folder, move items between folders, send messages stored in Outbox folder, view the contents in offline folders, and so on. OST files are basically replicas of your folders in your mailbox. And as soon as you connect to your mailbox servers or email provider, all the changes are automatically synced.

There’s also a Cached Exchange mode if you use an Exchange server email account. In this mode, the offline mode is automatically updated, allowing you to work seamlessly even with an absence of internet connection. It also automatically creates OST files as needed. The benefit of Cached Exchange mode is that it doesn’t ask you to manually set up send/receive groups, and therefore you don’t need to choose which folders you need to work when offline.

This eliminates the need of working “offline,” which is a different feature in Outlook altogether.

Due to the nature of OST files, you can often find these files inaccessible or damaged. If you are working offline but find that Outlook isn’t performing well or that the data is not sync to the servers properly, the most probably cause is that OST files are damaged. There are also cases where the OST file become inaccessible. That happens most likely by accidentally deleting the main account in Outlook to which the OST file was associated with. This makes the OST file useless, non-readable by Outlook, making the data stuck inside them.

This has always been a major concern for users. And the solution to recover OST files have always been half-measures by third-parties. But not anymore.

How to recover data from OST to PST

USL Software brings a tool called “OST Extractor Pro” that allows you to recover and convert OST files to PST files easily. Once done, you can simply import PST file to Outlook using the typical import/export feature and can get all your data back effortlessly.

It’s an easy to use tool with an intuitive interface. Even the least experienced basic home users can use it straightaway without any knowledge how email recovery or conversion works. That’s the magic of “OST Extractor Pro” and it’s friendly GUI.

And the best part, “OST Extractor Pro” has the most important feature necessary for any OST to PST converter tools. It has the powerful logic to extract and process the information without losing the data integrity. Which means, it is able to convert the smallest fragment of data like headers and metadata without compromising the fidelity.

Recover data from OST to PST

Download the free trial setup here. You can activate the full version anytime later after you have successfully evaluated the tool and are confident that it servers your purpose.