
PST stands for Personal Storage Tables. These Outlook data files manage and store mailbox folders including email messages, calendars, contacts, etc. on the local device. They can also be opened with different Outlook profiles and versions. Additionally, these data files are portable. All these factors may lead to corruption in these vital Outlook data file (.pst). Damage to these .pst files means operational glitches. The user will experience popping-up of error messages, difficulty in accessing inbox, issues with calendars, etc. So many issues! What to do next? The user must fix the damaged .pst files on the priority.
ScanPST.exe is the built-in functionality in Outlook. This free utility comes across all versions of the email client. It runs scans to unearth inconsistencies in the data file. After this, it diagnoses and repairs the .pst file. But it has certain limitations. The most prominent shortcoming is its inability to diagnose and repair a large data file (more than 2GB). It may not be able to fix severely-corrupted, inaccessible data file (.pst) as well. It may not be able to fully Recover Calendar Items. Such complex scenario demands a professional PST Repair Tool. To update more knowledge about this topic, stay tuned to our guide titled “Free PST Repair Tools vs Paid Software: Which Actually Works?”
What Does PST Corruption Mean?
As discussed earlier, this situation demands quick action. Any delay in fixing the file bugs may cause data loss. If the user fails to maintain the health of the .pst file, it may lead to the following issues:
- Missing Emails and Calendar Entries: A damaged .pst file can disturb normal operations, like the inability to access email messages, the disappearance of calendar appointments, etc.
- Corrupted Entries: It will also jumble up calendar entries like appointments, meetings, etc.
- Sudden Crashes: The app starts witnessing sudden freezes or crashes.
- Slow Processes: The normal time for any query, like inbox access, email message search, etc., increases.
- Risk of Data Loss: A corrupt .pst file can permanently damage sensitive information stored in mailbox folders.
How to Repair Outlook PST File for Free?
As the name suggests, such tools can be utilized without paying any charge. ScanPST.exe is a built-in utility. This free functionality is available with all Outlook versions. It runs multiple scans to detect error as well as inconsistencies in file header and structure. The step-by-step guide showcasing ScanPST’s functionality is discussed below:
Step 1: Search this utility on your system.

The location differs across Outlook versions. The below illustration will provide more clarity on ScanPST location:
| Version | Location |
| Office 365\2019\2016: | — 64-bit Outlook C:\Program Files\Microsoft Office\Office16 — 64-bit Outlook C:\Program Files\Microsoft Office\root\Office16 — 32-bit Outlook C:\Program Files(x86)\Microsoft Office\root\Office16 — 32-bit Windows C:\Program Files (x86)\Microsoft Office\Office16 |
| Office 2013: | — 64-bit Windows: C:\Program Files\Microsoft Office\root\office15 — 32-bit Windows: C:\Program Files (x86)\Microsoft Office\root\office15 |
Step 2: Close the Outlook app. Shutdown other app-linked processes and add-ins. Wait for some minutes.
Step 3: Browse ScanPST by double clicking its icon.
Step 4: After this browse the file path that you want to scan.

Step 5: A window showing the document library will open. Select the targeted file. Hit on the Open tab.

Step 6: Now press the ‘Start’ tab.

Step 7: The scan process progress will be appeared on a box window.

Step 8: When the process is done, the result will appear. Tick the check box to create pre-scan file backup. Click the ‘Repair’ tab.

Step 9: Hit on the ‘OK’ tab to conclude the repairs.

Step 10: Re-start the app. Now examine the repaired .pst file.
Why ScanPST May Not be Sufficient?
This utility is created to repair small files (upto 2GB). It may not be able to address bugs in complex corruption scenarios. ScanPST may fail to fix the following cases:
- Big Data Files: The tool may have trouble repairing a large data file. The user may face error messages like “ScanPST not responding.”
- Time Loss: The utility requires time and patience. It not only requires technical expertise but also needs enough time.
- May Not Fully Recover Calendar Items: It may not be able to fully recover calendar items like large attachments, files, etc.
- Partial Repair: ScanPST may leave some folders in the process. The utility may miss severely-damaged attachments or folders.
What is a PST Repair Tool?
This is a specialized software that is specifically developed to overcome the limitations of ScanPST. Such tool repairs and restores inconsistent folders like emails, contacts, calendars, etc. Tools like Stellar Repair for Outlook can fix all levels of corruption even an oversized .pst file (up to 50 GB). This advanced tool not only recovers calendar items but also missing email attachments with utmost precision. Powered with a friendly GUI, such software can quickly recreate the structure of a damaged file, thus saving loads of productive hours.
Key Highlights a PST Repair Tool:
Software like Stellar Repair for Outlook is recommended by experts for its quick repair speed. Some common features of this PST repair tool are listed below:
–Quickly scans the damaged file and recreates its structure.
— Can fix complex .pst issues in files of all sizes (up to 50 GB or larger).
— Ability to recover all calendar items (like missing appointments, meetings, etc.) as well as large email attachments.
— Unlike ScanPST where preview option is not available, Stellar provides the preview facility of the recovered items.
Free PST Repair Tools vs Paid Software: Which Actually Works?
Let’s understand this with the below comparison table:
| Features: | ScanPST | Stellar Repair for Outlook |
| Price | It is a free utility | It requires investment in the form of a licence cost. However, a free trial version is available with limited features |
| Expertise | Requires a bit of technical knowledge | Friendly interface, perfect for a person with limited technical knowledge |
| Capability to fix a large file | The best utility for small files. May struggle in fixing issues in a large .pst file (more than 2 GB). | Can fix large .pst files (50 GB and more) |
| Repair Speed | Slow as it runs multiple scans | Fast |
| Support | Limited | Full support available |
| File Export Formats | PST | EML, MSG, PST, HTML, PDF, etc. |
Conclusion:
We have discussed that ScanPST is a built-in functionality that comes with all versions of Outlook. This free tool scans file to identify bugs and later repairs them. But it comes with certain limitations. A big data file may surpass its repair capability. Similarly, it may fail to retrieve deleted email attachment or may not recover calendar items. We have also learned that we can surpass these limitations with a PST repair tool.
The above guide also unearthed a professional software Stellar Repair for Outlook. This repair software is advanced enough to even address issues that are beyond the capacity of ScanPST. It features a friendly interface. Its abilities to recover calendar items and deleted email attachments are awesome. Additionally, it can quickly decode bugs in even large data files (.pst).


