OST File Corruption Reasons and Solutions

Abhishek Pandey
Abhishek Pandey linkedin | Updated On - April 13, 2023 |

Read time 5 minutes

It’s not a matter of surprise to know the Outlook data files on your system can blowup at anytime.For offline work, your emails are stored locally on your machines, including the offline storage folders (yes, you read that right).

Outlook uses an offline folder file (OST file)to allow users to work offline, even if the Outlook program gets disconnected from MS Exchange Server. The OST file is a synchronized copy (cached Outlook items) of the mailbox saved on your server. Here’s the default location of the OST file: drive:\Users\\AppData\Local\Microsoft\Outlook.

Corruption is a common problem with Outlook data files when any unfavorable circumstances occuron the system.

Instant Solution

Try automated tool Kernel for OST to PST Converter to deal with OST file corruption issues and convert OST File to PST, EML, MSG, Office 365, and Exchange.

Native Solutions to Fix OST Corruption Problems

Solution 1: Update Folder

The method allows changing the properties of the folder (to clear offline items) to repair inaccessible OST File issues. Use the following instructions for MS Outlook 2010:

  1. Right-click the folder and click Properties.
  2. When the dialog box appears, click the ‘Clear Offline Items’ option under this dialog box.
  3. Click Ok.
  4. Now, click Send/Receive option in Outlook.
  5. Click Update Folder to save the changes.
Solution 2: Use Inbox Repair Tool

Inbox Repair tool (scanpst.exe) is a freesolution provided by Microsoft Outlook to fix minor glitches in Exchange OST and PST files. It allows the users to scan and repair OST files on Exchange Server and MS Outlook.This inbuilt tool helps the users manually fix minor corruption issues in the OST files.

You can use the Inbox Repair tool to repair errors of OST and PST files in the later versions of MS Outlook.Use Inbox Repair Tool

Limitations of Scanpst.exe tool

Free solutions come with certain restrictions, such as:

  • Able to fix only minor corruption problems.
  • No safety assurance while recovering the data.
  • Have to run multiple times to repair the file
  • Will not work with large OST files
Solution 3: Re-create the OST file

Microsoft Exchange Server uses an offline data file (OST), a copy of information stored on the email server. If somewhere you encounter issues with the OST file, you can delete the existing one and re-create (download) that again from the server. However, use this Re-create OST file procedure wisely, only if your OST file is not usable anymore. Also, there is a chance that you may lose the unsaved data if there are any.Re-create the OST file

Solution 4: Compress the OST file

A large size OST file may cause various troubles, such as OST corruption, sluggish Outlook performance, etc. And deleting some of the items may not bea viable technique to decrease the increasing file size. When you remove an item from the Outlook folder, then it still remains in the deleted folder. Deleting the item from ‘Deleted Items Folder’ will permanently remove it from the OST file, which is losing your valuable item. Another alternative to it is to compact the OST file. The OST file items are stored in such a way that they may occupy additional space and be unusable for other purposes. When you compact OST files, then it reduces that extra space occupied by the OST files.Compress the OST file

Solution 5: Start MS Outlook in Safe Mode

Starting Outlook in safe mode is to disable any add-ins that may throw errors during the booting process. It allows working safely without any files or add-ins being corrupt. Simply use this command to open MS Outlook in safe mode: “outlook.exe /safe.”Start MS Outlook in Safe Mode

Solution 6: Disable Anti-virus & Firewall settings

You can turn off the antivirus software and other firewall settings, as some programs (like Outlook) are designed to scan and detects problems for every incoming and outgoing email. Antivirus settings may block the normal functioning of Outlook at times, so you may try to disable the settings and restart Outlook to see the changes.

The Bottom Line

At times, corruption is unpredictable in Outlook data files,and that can restrict the user from performing normal functions. The native solutions aren’t a successful approach to completely rely on to deal with OST corruption problems. However, a third-party OST to PST converter solution uses a safe, secure, and swift method to recover severely affected OST files and convert OST to PST files immediately.

Rating by KHart85, Tech Outsourcing

Kernel for OST to PST