PST files are prone to errors and corruption. There are many reasons for PST file corruption. Some major causes are discussed below.

PST File Corruption due to Hardware Reasons

  • Bad Sectors on Hard Drive: It is a common error. When the local machine’s hard drive has bad sectors, PST files saved on it gets corrupted easily. So accessing them becomes impossible.
  • Network Issues: It is a practice these days to keep or save important data on a network server. But, what if network server or devices that connect to the server encounters an issue? The saved PST file will become inaccessible to the user. Situations like network failure or network breakdown might corrupt the PST file.
  • Sudden Power Failure: Unexpected power failure can cause PST file corruption. At the time of sudden power failure, if the PST file is open, it can become corrupt.
  • PST File Corruption due to Software Reasons

  • Malicious Software: Any malicious software installed or downloaded to your machine can lead to corruption of PST file data as well.
  • File System Recovery: If done incorrectly or at a wrong time, file system recovery can cause a real issue. If you have tried file system recovery in the wrong way, your files may get corrupt. This happens because file system disaster can interfere with PST files, resulting in permanently lost or overwritten PST files.
How to know if your PST is Corrupt?

If you are confused if your PST file is corrupted or have some other issue, then read further. Here we are going to mention a few popular error notifications a user with a corrupt PST file may face.

  • Errors have been detected in the file “filename”.pst. Quit Outlook and all mail-enabled applications, and then use the Inbox repair tool(Scanpst.exe) to diagnose and repair errors in the file. For more information about the Inbox repair tool, see Help.
  • The file “filename”.pst is not a personal folders file.
  • Microsoft Outlook has encountered a problem and needs to close. We are sorry for the inconvenience.
  • The file “filename”.pst could not be found.
  • Unable to display the folder. The file “filename”.pst could not be accessed. Access denied.
  • File “filename”.pst could not be accessed. Data error. Cyclic redundancy check.

Similarly, apart from these popular error notifications, there are many other error notifications you may face, indicating corruption in your PST file.

Instant Solution

After PST file corruption or damage issues, you need to repair and recover corrupt PST file data. By using PST repair tool you can repair and recover PST file data.

Here are some free PST repair tools that are recommended by experts:
Method 1: Repair with Inbox Repair Tool

The Inbox Repair Tool from Microsoft is a very simple tool which helps to repair the header of the PST file and delete the irrelevant details from the file that are not recognized by the tool. By default, this tool is located in one of the following locations:

If you are unable to find it in the above location for any reason, just go to Start and search for SCANPST.EXE. Still, if you face any issue, just download the Inbox Repair Tool from Microsoft’s website.

Follow these simple Steps after installing:

  • Step 1: Launch the Inbox Repair Tool, click Browse and choose the corrupt PST file, and click Start.
  • Step 2: After completion of the process, the tool will display errors found in PST file. Now, click Repair. The file repair begins. , Sometimes the file is not recovered and repaired in the first shot, so you willt have to repeat the procedure several times. After repairing, you might not face the same issues anymore in Outlook for accessing the PST file.

Although Scanpst is a free and readily available solution, sometimes it may not work. If the corruption levels of your PST file is way too much, this may not work for you. Apart from not working at all in your case, this Inbox Repair utility may also lead to many other errors. Here’s a list of a few selected errors that you may face while using this tool:

  • The Inbox Repair Tool does not recognize the file “filename”.pst. No information can be recovered.
  • An unexpected error prevented access to this file. Use ScanDisk to check the disk for errors, and then try using the Inbox Repair tool again.
  • The Microsoft Outlook Inbox Repair Tool does not recognize the file “filename”.pst. No information can be recovered.
  • An error has occurred, which caused the scan to be stopped. No changes have been made to the scanned file.
  • Fatal Error: 80040818
  • An unknown error prevented access to the file. Error 0x80070570: The file or directory is corrupted and unreadable”.

And many other known and unknown errors you may face while using this utility. If the corruption in your file is low, go for it.

Method 2: Truncate Oversized PST File

When the users launch MS Outlook (especially older version) and try to access PST files, you might face following error “Errors have been detected in the file > file_path >. Quit all mail-enabled applications, and then use the Inbox Repair Tool.”

The problem mentioned above occurs due to the exceeded size of PST file as the limit of Outlook data files is 2 B (in older Outlook versions).

Hence, to fix such a problem, reduce the PST file size so that it is in the specified limit. Use the Oversized PST and OST Crop tool by Microsoft which will delete some data from the PST file to reduce its size. Before using the tool, make a copy of the corrupt PST file as all the tool deletes some data.

While using this tool, please remember:

  • Your machine should have 2 GB of free hard disk space so that the tool can generate a copy of PST file.
  • Truncate the file between 20 to 25 MB less than the 2 GB limit. It will give you enough space for working.
  • This method is not 100 percent reliable. Also, truncated data will be missing from the original file.
Method 3: Best free PST Repair Tool

Using this free PST repair is one of the simplest and easiest ways to repair corrupt PST files. This tool offers some great features to repair a PST file.

  • Repairing of oversized as well as damaged PST files
  • Recovery of deleted messages and attachments
  • Saving in different file formats and destinations
  • Support for all version of MS Outlook

If you’re not able to find a PST file on your system, the Search option in the tool allows you search for a PST file in the entire Hard Disk. After recovery, you can save the PST file in the desired format and location. Also, you can save 25 items from each folder completely FREE.

How to prevent PST corruption?

Now when we have discussed almost every aspect related to a corrupt PST, let’s now know how you can avoid ending up with one.

  • Don’t let your PST file become oversized.
  • If you are working on Outlook or even if it is running in the background, don’t shut down your system.
  • It is recommended to save your PSTs from earlier versions in not more than 2gb size.
  • Don’t have a lot of emails. Try to manage them from time to time.
  • Carefully install add-ins.
  • Carefully install and use antivirus


The three best PST repair free solutions – Inbox Repair Tool, Oversized PST and OST Crop tool, and Kernel for Outlook PST Repair—helps you deal with PST and Outlook issues in three different ways. The first one helps to repair corrupt PST files, the second one helps to reduce the size of PST files, and the third one helps to recover Outlook PST data (25 items/folder free).