What Are OST and PST Files? | Outlook Data Files Explained

What are OST and PST?

Personal Storage Table (.pst) Files: These keep your data right on your computer, often tied to POP3 email accounts or used for archiving across different setups. You pick where they go—usually landing in C:\Users[Username]\Documents\Outlook Files. You can move or copy them yourself no problem.

Offline Storage Table (.ost) Files: Made for IMAP, Exchange, or Microsoft 365 accounts, these hold a synced copy of what’s on the server so you can use Outlook offline. The system decides their spot, typically C:\Users[Username]\AppData\Local\Microsoft\Outlook, and they’re locked to a specific profile, so you can’t mess with them directly.

These file types are the guts of Outlook, but they’re not invincible—power cuts, bloated sizes, or sync glitches can mess them up. Knowing how they tick is key to keeping your data safe and fixing issues when they pop up.

How Do Outlook Data Files Function?

Outlook data files are all about storing and pulling up your stuff, and they run differently depending on what they’re meant for.

Operation of .pst Files: These save data locally without always chatting with the server, except maybe for scheduled POP3 uploads. They stand on their own, syncing only when you tell them to or set them up that way.
Operation of .ost Files: These stay in touch with the email server, keeping everything matched up. When you write an email or book a meeting, it hits the .ost file and shoots to the server. Offline, you can still poke around in what’s already there, and it’ll catch up once you’re back online.

Significance of Outlook Data Files

Outlook data files are a big deal in the app’s world, bringing some real perks to the table.

Offline Access: With .ost files, you can check or tweak emails, calendars, and contacts without Wi-Fi, syncing it all later. .pst files, being local, just work offline naturally—no server needed.
Data Preservation: .pst files let you back things up by copying them to a USB or cloud storage, handy if your hardware tanks. .ost files lean on the server, but you can export them for extra safety.
Performance Impact: Big files can slow Outlook down. Keeping an eye on their size helps keep things running smooth and snappy.
Troubleshooting Utility: If your PST file gets corrupted, you might see errors, or the OST or PST file goes missing. Understanding how they work makes it easier to spot and sort out those headaches.

Fix: OST is Not an Outlook Data File Click Here

Management of Outlook Data Files

Here’s how to tackle the key tasks for keeping .ost and .pst files in check.

Locating Data Files

.pst Files: In Outlook, head to File > Account Settings > Account Settings > Data Files. You’ll see the list and paths usually C:\Users[Username]\Documents\Outlook Files.

.ost Files: The Same spot shows where they’re at, often tucked in C:\Users[Username]\AppData\Local\Microsoft\Outlook, but you don’t get much say in moving them.

Creating a New .pst File

To whip up a fresh .pst file:

In Outlook, click File > Open & Export > Open Outlook Data File.

Pick an existing .pst or
make a new one via New Items > More Items > Outlook Data File.
Name it, choose where it’ll sit, and hit OK to add it to Outlook.

How you can Import a PST File Click Here

Repairing Corrupted Files

To fix a corrupt Outlook file:

Shut down Outlook.
Locate SCANPST.EXE in the install folder (like C:\Program Files\Microsoft Office\root\OfficeXX).
Run it, pick the corrupt .pst file or .ost file, and start the scan.
If it finds trouble, hit “Repair” and wait it out, then restart Outlook.

When you are handling severely corrupt OST or PST files, that ScanPST couldn’t fix, Opt for a reliable third-party Outlook Repair Tool such as SFWare Outlook Repair Tool.

We recommend you download and try this tool without any hesitation as it works on a backup of your Outlook data file, so your file is untouched at any given point.

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How do you fix Outlook data files using the SFWare PST Repair Tool?

Step 1: Download, install, and open the SFWare PST Repair Tool.

Step 2: Select a PST file import method.

Open Default PST file: Imports default Outlook PST file.
Select PST File Manually: Manually Browse and select a PST file.
Find all Your OPST Files: The software scans the entire drive and lists all the Outlook data files from which you can choose.

Step 3: Select the scan, choose a destination path for the repaired PST file, and click on Repair.

Step 4: View the results summary and save the file if satisfied.

Also Read: How to Fix Corrupt OST File?

Reducing File Size

To trim Outlook data file with archiving:

Go to File > Info > Tools for Accounts > Clean Up Old Items.

Pick a folder (say, Inbox), set a cutoff date for old stuff, and choose a .pst file to stash it in.
Confirm it, and the old data moves over, lightening the load.
Sticking to these habits keeps your Outlook data files steady and speedy.

Conclusion

Outlook data files are the heart of Microsoft Outlook, handling the storage and retrieval of user info across all kinds of accounts. This piece has broken down what they are, how they run, why they’re useful, and how to manage them.

What is an Outlook Data File?