Repair corrupted PST file: the complete fix guide

For most working professionals, Outlook is a cornerstone that streamlines your workflow allowing you to manage emails, notes, schedules, and more!

However, there may come a day when you can’t access your Outlook profile. You won’t be able to send or view sent emails, and lose access to any of the Outlook items that you regularly depend on.

This is usually caused by a damaged or corrupted PST file. You will need to repair your PST file fast as you stand a chance of missing out on important emails and more. Here, we will teach you everything that you need to know about PST files and how to repair them!

What is a PST File?

A Personal Storage Table file (or OST for short) is a file format that is used to store all your Outlook data such as notes, calendars, emails, and more! The Outlook application works with PST files to allow you to send emails, schedule emails, or create a reminder.

While the Outlook application is responsible for sending emails or creating notes, Your PST file is the reason you can store the emails you receive, or save notes to be read at a later date. Without your PST, you would not be able to take advantage of any Outlook features.

Symptoms of a Corrupted PST File

Here are some signs that may indicate that your PST file is damaged or corrupt.

1. Unable to Open Or access Outlook.
2. Unable to Open or View Sent emails.
3. Unable to find your PST file.

Note: If you are experiencing any of the above or related symptoms, make sure to export your Outlook PST file and try using it on a different system to confirm that the issue lies with the PST file and not the Outlook application.

PST vs OST: which repair steps apply to your account?

A PST is a file that lives on your local machine and contains all your Outlook data. An OST is a local cache of a mailbox that actually lives on a server, either Exchange or Microsoft 365. That distinction matters because the repair approach is completely different, and running ScanPST on an OST is often the wrong move.

If your Outlook account connects to Microsoft 365, Exchange, or an IMAP server, you have an OST. You will not have a PST unless you created one yourself as an archive. The simplest way to check: open Outlook, go to File, then Account Settings, then Account Settings again, and click the Data Files tab. Files ending in .ost belong to server-based accounts. Files ending in .pst are local stores. Every repair step on this page applies to .pst files only.

A corrupted OST is usually easier to fix than a corrupted PST, because the server holds the master copy. Close Outlook, navigate to the OST file (typically at C:\Users\YourName\AppData\Local\Microsoft\Outlook), rename it with a .old extension so Outlook cannot find it, and reopen Outlook. Outlook will rebuild the cache from the server. Your data comes back from Microsoft 365 or Exchange, not from the damaged local file. You do not need ScanPST for this, and you do not need a third-party tool. The catch is that this only works while the server is reachable and the account is active.

One scenario that trips people up: a Microsoft 365 account where someone also manually created a local .pst archive. In that case you will see both file types in the Data Files tab. The OST handles itself via the server rebuild method above. The .pst archive is a separate file and needs to be repaired on its own if it is damaged. Treat them as two independent problems, not one.

What causes PST file corruption?

The most common cause is an abrupt shutdown. Outlook writes to the PST file continuously while it is open, and if the process is killed mid-write, by a power cut, a hard reboot, or Windows Update forcing a restart, you can end up with a partially written record that breaks the file’s internal index. A single interrupted write is usually enough.

Oversized files are the other one I see regularly. Outlook 2016 and later support PST files up to 50 GB, and in practice performance starts degrading well before that, around the 20-25 GB mark. At those sizes, even routine compaction operations are more likely to leave the file in a bad state if interrupted. If you have hit common PST file issues around slowness or missing items, checking the file size is the first thing I would do.

Network drives are a less obvious culprit. Storing a PST file on a mapped network drive or a NAS is not supported by Microsoft, and the reason is latency: Outlook expects near-instant disk writes, and a slow or intermittent network connection introduces gaps that corrupt the file structure over time. It can take weeks before the damage becomes visible. Antivirus software scanning a PST mid-write causes the same class of problem, which is why every major antivirus vendor recommends excluding .pst files from real-time scans.

Hardware failure can also do it. A PST sitting on a drive with developing bad sectors will accumulate errors silently until Outlook throws an error you cannot dismiss.

Can you fix a corrupt PST file?

One thing I like about our problem here is that there are effective solutions that we can rely on.
The solutions below are arranged in terms of effectiveness and I suggest that you try both in order.

1. Repair PST File with ScanPST (Inbox Repair Tool)
2. Repair PST File using Rikvr Repair For Outlook

While both methods are user-friendly and easy to use, I would request my readers to go through all the steps before proceeding.

During the repair process, please prevent any interruptions as a precaution.

My PST file is corrupted. How can I fix it?

Run ScanPST.exe first. It is free, it is already on your machine, and for most straightforward corruption it is enough. Find the executable at the path that matches your Outlook version (listed in the section above), close Outlook completely, then point ScanPST at your .pst file and click Start. The scan will tell you whether it found errors. If it did, click Repair.

ScanPST does have a ceiling. Files that have grown past about 50 GB, or that have suffered physical-level damage from a failing drive, tend to come back with partial recoveries or fail the repair step entirely. I have seen it return a technically repaired file that would not open in Outlook because the header was still inconsistent. That is when a dedicated Outlook PST repair tool becomes the practical next step rather than an optional upgrade.

One thing worth knowing before you start: ScanPST creates a backup of your PST before it writes any changes, and that backup sits in the same folder with a .bak extension. Do not delete it until you have confirmed the repaired file opens correctly and the folders inside it look right. If the repair makes things worse, you can rename the .bak back to .pst and start over.

If you are not certain ScanPST is the right route, or you want to understand the options before committing, the guide on how to repair PST files without ScanPST covers the cases where the built-in tool falls short and what to do instead.

Where to find ScanPST.exe for every Outlook version

The Inbox Repair Tool location changes with every major Outlook release, and this is the question I see cause the most confusion. People find the right instructions but look in the wrong folder, convince themselves ScanPST is missing, and download something unnecessary. It is not missing. The path just depends on which version of Office you have installed.

For Microsoft 365 and Outlook 2016 or 2019 installed via Click-to-Run (the default for most users since 2016), ScanPST.exe lives here:

• 64-bit Office: C:\Program Files\Microsoft Office\root\Office16\SCANPST.EXE
• 32-bit Office on 64-bit Windows: C:\Program Files (x86)\Microsoft Office\root\Office16\SCANPST.EXE

For MSI-based installations, which were common in volume-licensed environments before 2019, the SCANPST.EXE path for Office 2019 and 2016 is slightly different:

• 64-bit Office 2016/2019 MSI: C:\Program Files\Microsoft Office\Office16\SCANPST.EXE
• 32-bit Office 2016/2019 MSI on 64-bit Windows: C:\Program Files (x86)\Microsoft Office\Office16\SCANPST.EXE

Outlook 2013 used Office15 in the folder name rather than Office16. So the Click-to-Run path becomes C:\Program Files\Microsoft Office\root\Office15\SCANPST.EXE. If you are still on Outlook 2013, the structure is the same but that one number changes. Not sure which you have? Open any Office application, go to File, then Account, and look under About. It tells you the exact build and whether it is Click-to-Run or MSI.

The fastest way I have found is to open Windows Explorer, paste the likely path into the address bar, and see whether the file is there. If it is not, use the Windows search box in File Explorer, search your entire C: drive for SCANPST.EXE, and let it surface the correct location. That takes about thirty seconds and removes the guesswork entirely.

How can I repair a PST file for free?

Stuck with a damaged PST file? Do not worry, Microsft has you covered. Along with the Outlook application you ScanPST as well!

What is ScanPST?

Also known as the Inbox Repair Tool, ScanPST is a PST repair utility that is specifically designed to repair corrupt PST files and restore them back to how they used to be. It has several advantages.

Benefits of ScanPST

• It is extremely easy to use. (even for beginners)
• ScanPST comes pre-installed with Outlook.
• It is a free PST repair tool.
• It is effective in fixing minor PST file errors and inconsistencies.

Where Is ScanPST Located?

While ScanPST’s location is no secret, it may be slightly tricky to access, I have provided the file location of ScanPST in the list below-

1. Outlook 2021: C:\Program Files\Microsoft Office\root\Office16
2. Outlook 2019: C:\Program Files\Microsoft Office\root\Office16
3. Outlook 2016: C:\Program Files (x86)\Microsoft Office\root\Office16

How do I repair my PST file using ScanPST?

Locating ScanPST is usually the hardest part, after which it’s just smooth sailing. All you need to do is open ScanPST and follow the steps below-

Note: Before starting, quit Outlook and all mail-enabled applications to diagnose and repair errors in the file.

1. After opening ScanPST, Click on Browse… and import your corrupted Outlook PST file. Then, Click on Start to confirm your choice and begin the scanning process.

2. The Scanning process will examine your PST file for any errors or inconsistencies. If any are found, there are 3 things that you need to do.

1. Check the box to create a backup of the scan file before repairing
2. Click on Browse… to select a save location and name the backup file.
3. Click on Repair to confirm your choices and begin the PST repair process.

3. After the Repair process, all that is left is to verify if ScanPST was able to repair your damaged PST file.

Why Won’t ScanPST Work?

While ScanPSt is a great tool, it does have a few drawbacks-

1. Cannot repair severely corrupted PST files.
2. Only works on PST files that are 2GB or smaller.
3. Works on the original PST file making it vulnerable to irreversible changes.
4. Manually locating and importing your PST file may be tough.

For a more effective PST repair solution, we can use specialized tools like professional PST repair software.

2. Repair PST File using Rikvr Repair For Outlook

When ScanPST won’t work, a professional PST repair tool is a good option. Third-party PST repair tools are a better option as they are easier to use and more effective compared to the inbox repair tool.

Here, we will be using Rikvr Repair For Outlook, its user-friendly design, advanced repair algorithm, and preview options make it a great solution to fix corrupted PST files.

How do I repair my PST file using Rikvr Repair For Outlook?

1. Import the Corrupted PST file

• Open Default PST File- Imports PST file from default location
• Select PST File Manually- manually browse and select the corrupted PST file
• Find All Your PST Files- The software scans the entire drive and lists out all the available PST files for you to choose from.

2. Choose a scanning method, select a save location, and click on Repair to begin the repair process.

3. Save the repaired PST file and verify the results.

How to repair corrupted PST file on Windows 10 and Windows 11

The repair process itself is the same on both. The difference is where you find ScanPST and how you navigate to your PST file, because Windows 11 moved a few things around in File Explorer.

On Windows 10, the AppData folder is hidden by default. In File Explorer, click View in the ribbon, then check Hidden items. Your PST file will typically be at C:\Users\YourName\Documents\Outlook Files for POP3 accounts, or C:\Users\YourName\AppData\Local\Microsoft\Outlook for older profiles. On Windows 11, the View menu became the three-dot menu in the top bar. Click it, hover over Show, and select Hidden items from there.

To repair corrupted PST file on Windows 11 specifically, one thing catches people out: if you installed Outlook from the Microsoft Store rather than from a standard Office installer, the ScanPST.exe path is different. You will find it under C:\Program Files\WindowsApps, inside a folder with a name starting with Microsoft.Office.Desktop. That folder is access-restricted by default, and you will need to take ownership of it before you can run anything inside it. Most people in that situation are better served by using Rikvr Repair For Outlook directly rather than fighting Windows folder permissions.

For Windows 10 with a standard Office installation, if you need to confirm the Outlook PST file location before you start, File, Account Settings, Account Settings, Data Files tab will show you the exact path of every data file Outlook currently has open.

PST size limits and what happens when you exceed them

Outlook 2016, 2019, 2021, and 365 all share a 50 GB default limit for PST files. You can raise it via a registry edit, but Microsoft does not recommend it, and neither do I. Past 50 GB, the file becomes increasingly fragile and ScanPST takes longer to scan it, sometimes hours on a mechanical drive.

The older Unicode PST format used by Outlook 2003 and 2007 had a 20 GB limit. If you are working with an archived PST from that era, that is the ceiling to be aware of. Go above it and Outlook simply refuses to open the file.

The ANSI format, used by Outlook 97 through 2002, capped out at 2 GB. That sounds like a non-issue in 2025, but I still see people open a twenty-year-old archive and hit exactly this wall. Outlook shows a generic “file is not a personal folders file” error rather than telling you the file is full, which sends people down the wrong repair path. The file is not corrupt. It is full.

If your PST is approaching its limit, the cleanest solution is to archive older items into a second PST and keep the active one under 10 GB. Compact the file afterwards: File, Account Settings, Account Settings, Data Files, Settings, Compact Now. This reclaims space from deleted items that Outlook has marked as deleted but not yet removed from the file structure. A 15 GB PST that has had half its mail deleted can shrink to 8 GB after compaction.

Avoiding Future PST File Catastrophes

The trick to protecting yourself from the dangers of losing your Outlook PST file and the contents in it is to adopt appropriate precautions

• Regular backups- creating and regularly updating a PST backup file will protect you during a data loss scenario.
• Keeping PST files under recommended size limits- If you notice your PST file reaching its storage limit, you may want to take appropriate measures as you stand to face performance issues.
• Properly closing Outlook before shutting down the computer – abruptly shutting down your Outlook application may damage your Outlook data file.

To Conclude

While damaged Outlook PST files can cause several issues, we can always seek comfort in the fact that there are ways to resolve these problems in the comfort of our desks. I hope that you were able to repair your PST file and restore it back to health. If you have any feedback or related queries, please do reach out.