How to Fix Corrupted Outlook OST File?

Offline Storage Table simply called as OST file, is a Microsoft Outlook storage file. The benefit of OST file is that it allows users to continue their work on Outlook even if the application is disconnected from Exchange Server or in offline mode. You can compose new emails, save them in drafts, read or delete existing emails, etc. Once the internet connection is retrieved, whatever changes you have made to the Outlook OST file gets automatically synchronized with Exchange Server. Actually, OST files are a carbon copy of mailbox lying on Microsoft Exchange Server and are stored in computer hard drive. Therefore, damage to Exchange Server does not affect OST file saved on your hard drive.

But several times, you may get error messages while synchronizing your Offline Folder file (.ost). Sometimes you might also notice that some of your items are either deleted or missing. It usually happens due to human error or OST file corruption. So, if you suspect that your OST file is corrupt, then you need to use OST Integrity Check tool (Scanost.exe) to fix your MS Outlook OST file.

OST Integrity Check Tool

The OST Integrity Check is a Microsoft inbuilt repair application used to diagnose and repair OST file. The tool works by scanning both your OST and mailbox file running on Exchange Server. It compares items and folders in each file and attempts to resolve synchronization differences between them. To use this tool you must be connected to your Exchange account server.

Fixing Errors Using Scanost.exe

  • Terminate MS Outlook before starting repair process
  • Open Scanost.exe by double clicking on it, the default location is at drive:\Program Files\Microsoft Office\OFFICE12
  • If you have multiple Outlook accounts, the tool will prompt you to choose the OST file that you need to repair
  • If you are asked to Connect or Work Offline, click Connect
  • Choose the option according to your need
  • Select “Repair Errors” checkbox to automatically resolve errors while scanning OST file
  • At last click “Begin Scan”

Limitations of Scanost.exe

There are few drawbacks, which are related to OST Integrity Check Tool like:

  • Capable of repairing only minor corruption issue
  • Do not recover data from OST file
  • There’s no guarantee for the safety of the data
  • The tool is unavailable in Outlook 2010 or later release

Automated Method to Fix Corrupt OST

Nevertheless, you cannot fully rely on this inbuilt tool to repair corrupt OST, as it has limitations. So, in such cases, you need a professional tool. One such tool is Yodot Outlook PST Repair. This tool is amongst the best repair utilities ever to fix your OST file corruption due to any reason. The best thing about using this software is that after repairing OST file, it recovers all deleted or lost items like emails, Attachments, Notes, Journals, meeting requests, etc. The tool scans corrupted OST, copy its contents to a new file and fix issues; thus keeping your original file intact.

Along with OST, the tool supports corrupted PST file repair. And while moving your PST to another physical location through USB drive, things can go wrong making your pen drive corrupt. In such instances instead of thinking why my pen drive is corrupted and unreadable you can make use of Yodot data recovery product to reach your PST and other files on USB flash drive with utmost ease.

Process to Repair Corrupt OST File

  • Download Yodot Outlook PST Repair and install the software on your computer
  • Open the software and follow main screen procedure
  • Use “Open PST File” option to browse for your corrupt OST file which is to be repaired
  • Click on “Find PST File” option to search for the OST file
  • Select “Outlook Profile” option to choose for a particular Outlook profile if you have multiple Outlook accounts
  • Select “Normal Scan” method to fix your OST file with minor corruption or choose “Smart Scan” method to fix your severely corrupted OST file and click on “Repair” button
  • The application initiates the repairing process, after which it shows all the recoverable items in Outlook styled interface

Things to be noted:

  • Close all MS Outlook elements before the repair process
  • Never exit your Microsoft Outlook application improperly
  • Use a quality antivirus program to remove virus from your system
  • Backup your OST file regularly

Other Popular Software

Yodot File Recovery (Windows)

Recover deleted, lost office files, PDF documents, images, database, emails and other file types using the fastest file recovery software for Windows. Download the free trial of the software and evaluate the chances of recovery.


Yodot Hard Drive Recovery (Windows)

Accidentally formatted a partition / drive on Windows. Recover data from accidentally formatted FAT, NTFS partitions and restore them to another healthy partition.