Tag Archives: ost to pst

When working on MS Outlook 2003 or later versions, the user is provided with an enhanced feature for offline folder called – Cached Exchange Mode. This feature offers the smooth synchronization and offline operations between Exchange Server and Outlook. However, due to the sensitive nature of offline folder (OST files), there are frequent chances of corruption. At times, when your Exchange mailbox or offline folders are not in inconsistent state, then the user may face the following error:

“Exchange is currently in recovery mode. You can either connect to your Exchange server using the network, work offline, or cancel this logo”

The above-mentioned error message describes that Exchange Server and Outlook are currently in recovery mode. In this situation, the user is provided two options for recovery, which are:

  1. Online Mode: When you select ‘Connect’, then you can access Exchange Server, but not the old OST files. However, if you wish to access the mailbox data from old OST files, then you need to exit from MS Outlook program and switch to other option offline mode.
  2. Offline Mode: This ‘Work offline’ option lets you to access your old OST file data in offline mode. However, this option does not let you access Exchange Server.

With the above-featured options, the user can successfully access data of OST files or new mailbox data available on Exchange Server.

How to Exit from Exchange Recovery Mode Issue and Get Your Outlook Back to Normal Functioning

    1. Close MS Outlook program and rest of the programs using the old OST file.
    2. Search your old OST file, by using the Search function in Windows bar, or simply find the old OST file in the default location for the offline folders.
    3. Before moving further, it is important to back-up your old OST file for the sake of safety and avoid losing your essential data.
    4. Now, turn off the Cached Exchange Mode option.
      • Launch Outlook program.
      • Reach Tools menu, and click E-Mail Accounts, and then go to View or change existing e-mail accounts option, and click Next to proceed further.
      • When Outlook processes e-mail for these accounts in the following order list appears, then select Exchange Server e-mail account, and choose Change option
      • Select to clear the Use Cached Exchange Mode check box, under Microsoft Exchange Server option.
      • Close MS Outlook application.
    5. Now you can rename or delete your old offline folder (OST) file.
    6. Enable Cached Exchange Mode option.
      • Launch MS Outlook application.
      • Go to Tools menu, select E-Mail Accounts. Go to View or change existing e-mail accounts, and then click Next to proceed further.
      • When this list appears ‘Outlook processes e-mail for these accounts in the following order’, then select Exchange Server e-mail account, and select Change
      • Turn on the Use Cached Exchange Mode check box, under Microsoft Exchange Server.
      • Close MS Outlook program.
    7. Rebuild a new OST File. Restart Outlook and make sure the settings for the new Exchange mailbox account in Outlook are correct, and Outlook can connect to your Exchange server successfully. Then send/receive your emails on the corresponding Exchange mailbox, which will let Outlook create a new offline folder file automatically and synchronize its data with the Exchange mailbox.If this method doesn’t work, then your current mail profile is incorrect, and you must delete it and create a new one, as follows:
      • Exit Microsoft Outlook program
      • Go to Start, and then select Control Panel.
      • Select Switch to Classic View, in case you are working on Windows XP or later versions.
      • Double-click Mail.
      • Under the Mail Setup dialog box, select Show Profiles.
      • Choose the incorrect profile from the list and select Remove option to remove it.
      • Repeat step 6 until all the incorrect profiles have been removed.
      • Select Add option to make new profile and configure email accounts as per their settings on the Exchange server.
      • Launch MS Outlook and then resynchronize your Exchange mailbox. Now exit Exchange Recovery Mode.
    8. You can now import recovered OST data after you have exit Exchange Recovery Mode

However, if the above-mentioned problem is unsuccessful to resolve this issue, then trust a third-party OST to PST software to repair corrupt OST file and then convert it to PST file – in order to make your Outlook mailbox accessible immediately. Recoveryfix for OST to PST is a user-friendly tool to recover lost/inaccessible data from OST files and then convert to PST files successfully in a single attempt.

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Outlook Data Files are of two types – OST (Offline Storage Table) and PST (Personal Storage Table). OST files allow you to access MS Outlook mailbox items during unavailability of internet (when MS Outlook is not connected to the Exchange Server). Whatever changes you make during offline mode, get synchronized automatically whenever internet connectivity is back.

Talking about data corruption, OST files get corrupted easily. And, OST corruption can lead to data loss if not fixed immediately. Before knowing about fixing OST corruption issues, you should know the most common reasons for the same.

OST corruption is most likely to occur due to:

  • Bad sectors on your system’s hard disk where OST files are stored
  • Data synchronization issues between OST files and Exchange Server
  • Failure of data storage devices
  • Network connection issues
  • Improper Outlook termination or upgradation to a higher version
  • Virus attack, abrupt system shutdown or sudden power failure, etc.

Outlook mailbox cannot be accessed during OST corruption. Depending upon the cause of corruption, different error messages are likely to appear on your computer screen if you try to access mailbox items during OST corruption. Here are the most common error messages you might get while trying to open corrupt OST files:

  • “Unable to expand the folder. The set of folders could not be opened. Errors could have been detected in the file xxxx.ost. Quit all mail-enabled applications, and then use the Inbox Repair Tool.”
  • “Cannot open particular Outlook items when offline”
  • “Cannot open your default email folders. The file xxxx.ost is not an offline folder file.”

How to fix OST corruption?

Error messages is good enough to make you worry about your data. However, there is no need to get worried. OST file corruption can be fixed easily. You can either use native Inbox Repair Tool (Scanost.exe) or a professional OST to PST Converter tool to fix OST corruption issues. First, try using native tool.

Inbox Repair Tool (Scanpst.exe/Scanost.exe)

Microsoft provides Inbox Repair Tool along with its MS Office suite. Also known as Scanost.exe tool, it’s capable of fixing minor OST corruption issues. It’s absolutely free. To use it, follow the below given steps:

  1. Open – drive:\Program Files\Microsoft Office\OFFICE (version)
  2. Double-click Scanpst.exe/Scanost.exe to open it
  3. Type the name of the file you want to repair or Browse it.
  4. Select Repair checkbox and click on Start Scan.
  5. The scanning process begins.

Once it’s over, open Outlook and go to Folder List. Repaired OST files can be seen inside the folder named Recovered Folders List. And if not, you need to use a professional software.

Inbox Repair tool is incapable of repairing severely corrupt OST files. And, there is no guarantee of complete and accurate data recovery. Thus, using a professional OST recovery tool is the best way to recover corrupt OST files. Recoveryfix for OST to PST, is a prominent tool to recover corrupt OST files. It swiftly fixes all OST corruption issues regardless of the cause of the corruption and recovers entire Outlook mailbox data.

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It uses its two robust scanning modes – Standard mode and Advance mode to scan corrupt OST files. You can save the recovered data in different formats such as PST, EML and MSG. The software also lets you save email messages in HTML, RTF and Plain Text format. The software comes with LIVE update feature (automatically updates the software with the latest version).  And, it’s compatible with most of the versions of MS Outlook including 2013, Outlook Express 5.0 and above and MS Exchange Server including 2013. The too is incredibly easy to operate because of its user-friendly interface.

How to Recover Outlook Data File OST

Recover Corrupt Outlook OST file data using a professional tool

Follow below steps one-by-one:

  1. Open RecoveryFix OST to PST software tool.

Below is tool’s home screen, there two steps,
Step 1 – to select the corrupt OST file.
Step 2 – to select the recovery mode.
select the recovery mode

  1. Select the corrupt Outlook OST file.
  2. Select the corrupt Outlook OST file

  3. Select the Recovery Mode, select Standard Mode.
  4. Note: Recovery Mode selection depends upon the level of corruption, for serious file corruption you should select Advanced Mode.
    Recovery Mode selection

  5. Click Next,
  6. The tool will scan the corrupt or damaged Outlook OST file.
  7. Note: Time for scan completion depends on the total size of the OST file.
    scan completion depends on the total size of the OST file

  8. Upon the scan process completion, tool’s interface would refresh and load three different sections which are
    file tree structure view – in the left, folder view – at the top, message view – at the bottom,
  9. Note:
    In the file tree structure view, you can expand or collapse any folder – empty or containing file(s) and select as per the requirement.
    Clicking on the specific folder(s) would list the folder contents – items.
    Clicking on specific emails – messages, you can view the email, this feature is Live Preview.
    Live Preview

  10. Select all the folder(s) as per your requirement or select the master (root) check box, as shown below, to recover mailbox file(s) & folder(s),
  11. Select all the folder(s) as per your requirement

  12. Once you’re done with folder(s) selection, click Save.
  13. In the Saving Options Screen.
  14. You can select between saving the file to Outlook or Outlook Express and choose between keeping the recovered data in PST file or MSG file format and lastly picking the file location/path to save it.
    Note: If you wish then you can remove IPM_SUBTREE from the hierarchy in Outlook, and in case if you don’t possess enough technical knowledge then leave the option as it is.
    Check/Uncheck the Attach Prefixes to Store Name.

  15. Click Ok, when you’ve finalized the save settings.
  16. Click Ok

  17. Total Time required for Saving Process depends on the actual size of Outlook OST data file,
  18. Note: You can stop the saving process anytime if you’ve done something wrong during the whole process.
    something wrong during the whole process

  19. Finally, click OK.
  20. Finally, click OK

Offline Storage table or OST is a file format to store Exchange mailbox information when MS Outlook fails to establish connection with Exchange Server. OST file synchronizes with MS Exchange Server soon after Outlook is reconnected with Exchange network. But presence of several factors in the MS Exchange environment halts OST synchronization process. These factors are mentioned below :

  • Virus, spyware and adware codes
  • Unexpected system shutdown
  • Exchange Server crash
  • Internet disruption for long time
  • Abnormal OST file size
  • Computer hardware malfunctioning
  • Corrupt or missing Windows system file
  • Several Outlook profiles on client Server

OST Synchronization errors

  OST corruption or synchronization failure is highly undesirable event in large IT organizations who use MS Outlook client for email communication. One of the common OST synchronization errors is shown below:

Unable to expand the folder. The set of folders could not be opened. Errors could have been detected in the file pqr.OST. Quit all mail-enabled applications, and then use the Inbox Repair Tool

Here pqr.OST represents an Exchange OST file that shows abovementioned error message.

Recommended Solution
Use Recoveryfix for OST to PST Converter to fix error ‘Unable to Expand folder’ and other issues related to an OST file.


You should check whether there are multiple Outlook profiles for a single account and delete all profiles from your system.  Then you can recreate a new Outlook profile using following steps:

  1. Click Windows start menu
  2. Go to Control Panel>Mail
  3. Hit “Show profiles” in the new Windows
  4. Press “Remove” button to delete old Outlook profiles
  5. Click “Add” to create a new Outlook profile and press “Ok” button
  6. Click “Manually configure Server Settings or additional Server types”  in the new Windows and press” Next
  7. Add your Exchange account address and press “Next
  8. Click “Finish” to  complete creation of Outlook profile
  9. Restart MS Outlook to  synchronize with Exchange Server

If the above mentioned option does not cure OST synchronization error then it may be generated due to hardware failure or other reasons. Microsoft Outlook is provided with inbuilt tools scanost.exe and scanpst.exe to cure database corruption. Scanost tool is also known as OST integrity checker and fixes many OST synchronization errors. OST integrity checker tool is stored in local MS Office folder of a Windows Server. You’ll not find scanost.exe in the system that uses Outlook 2010 or Outlook 2013. Default location of scanost.exe is:

C:\Program files\Microsoft Office\ Office 12\scanost.exe

Now start repairing corrupt OST file using following steps:

  • Close MS Outlook if it is running
  • Double click on Scanost.exe program
  • Select Outlook profile from your system that is linked with your Exchange account
  • Click “Connect” if  options “Connect” or “Offline” appear on your computer screen
  • Select “Scan all folders” option and also check “Repair errors” check box
  • Click “Begin Scan”  to start repairing selected OST file
  • Close scanost program

However, OST corruption due to Exchange Server crash, hardware malfunctions or other factors cannot be fixed by scanost tool or other manual options. In such circumstances, you will have to use an automatic OST to PST Converter tool to fix OST errors.

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RecoveryFix for OST is an ideal solution to all OST corruption issues. It recovers whole Exchange mailbox from a corrupt OST file and stores recovered mailbox information in the PST file.  This OST repair tool can also restore deleted Exchange accounts of a Server. It successfully recovers mailbox data even from password protected, compressed and highly encrypted OST files.


OST synchronization errors are generated due to various factors such as virus attacks, hardware malfunctioning and others. There are various manual options to fix OST corruption such as creation of new Outlook profile and OST integrity check tool. However, manual recovery of OST files is not successful in many cases. You must choose automatic OST Repair tool to fix critical OST corruption issues.

 4 Simple Ways to deal with ‘Errors have been detected in the OST’

In Outlook 2016 or 2013, users may get the error message ‘Errors have been detected in your .ost file’. The exact message that will appear on your screen is:

“Errors have been detected in the file C:\Users\<name>\AppData\Local\Microsoft\Outlook\user@org.com.ost”

It implies that your Offline Outlook Data File (OST) is corrupted. You can deal with this issue in different ways as give here: (more…)

Offline storage table (OST files) allows Outlook user to work conveniently even in the offline mode, because of the capability to synchronize and restore the offline updates on to the server without troubling the users. Besides the offline working convenience, OST file serves as a crucial data backup for user mailbox when the user has accidently deleted the mailbox items. However, the problem arises when corruption enters the OST files from the influence of hard disk crashes or the virus attacks. (more…)

Exchange server serves a carriage for MS Outlook, which carries Offline work of the user, and delivers it on finding its destination. The process of delivery is called synchronization process, which is obligatory to perform in order to maintain the Outlook database. The offline work is maintained in form of Offline storage table that are termed as OST files. On one hand, OST files are advantageous for MS Outlook users and on the other hand, they can be hazardous as they are prone to corruption.

Microsoft Outlook started gaining popularity since its inception, due to the usefulness and broad applicability of its features. MS Outlook is used extensively by individuals as well as organizations for email management. It stores data in the Personal Storage Table (PST) database file format. However, when used in cached mode or in offline mode with Exchange, then the data is saved in the OST file format. One works in offline mode when the server is not connected. While working offline, the changes made offline get reflected in the server after it is connected again.

Sometimes, work so done in offline mode and saved in the Offline Storage Table (OST) file might get corrupt due to various reasons. It becomes not possible to import or read an OST file in MS Outlook. A possible workaround this situation would be to use of third-party OST to PST Converter tool, that can help you gain access to your OST file(s) again, without losing on any critical data. However, before you know more about the OST to PST conversion here are some of the cases where you might be required to use OST to PST tool:

  • OST file has gone corrupt or damaged, and there are individual unsent emails that must be recovered
  • Some data in the OST file has not been synchronized with Exchange Server
  • Exchange Server is down, and therefore the OST file is unable to synchronize
  • User mailbox is shifted or deleted from its original location
  • An Exchange Server system is shut down
  • Name of the Exchange Server or user mailbox is changed
  • When you have decided to close an existing Exchange account but before that, you would very much like to export all the mail items to a PST format. Which can later be accessed by importing these files in an Outlook desktop client.
  • Note: The retention period to restore your Exchange mailbox is about to expire. Therefore, exporting to a PST file is essential before the mailbox is permanently deleted.

    We will discuss the use of Recoveryfix for OST to PST converter tool to overcome the situation of OST data inaccessibility. If you suspect minor corruption issues with your OST files, then it is worth checking the inbuilt Inbox repair tool (scanpst.exe), which comes preinstalled with Outlook and can be used to repair both PST and OST files. Depending upon the Outlook version, scanpst.exe can be found here-

    In Outlook 2019: C:\Program Files (x86)\Microsoft Office\root\Office16

    In Outlook 2016: C:\Program Files (x86)\Microsoft Office\root\Office16

    In Outlook 2013: C:\Program Files (x86)\Microsoft Office\Office15

    In Outlook 2010: C:\Program Files (x86)\Microsoft Office\Office14

    In Outlook 2007: C:\Program Files (x86)\Microsoft Office\Office12

    Recoveryfix for OST to PST Converter

    Recoveryfix for OST to PST allows you to Convert OST to PST so that the data becomes accessible again with MS Outlook.

    Download Now

    Now we will discuss the step-by-step procedure to convert OST to a PST file format. The steps are outlined below:

    1. After launching the tool, you are greeted with the welcome screen prompting the user to browse for the OST file(s). Next, one can choose from the two scan options depending upon the level of corruption. Choose Standard Mode if your OST file is healthy; if not, then choose the Advanced scanning mode.
    2. Select the  scanning mode

    3. The tool will now show you the OST mailbox items whilst preserving the data hierarchy. The mailbox items can be viewed prior to saving in the Preview pane.
    4. show you the OST mailbox items whilst preserving the data

    5. Next, the user can tune a few parameters/ apply filters prior to saving the output file. Click, OK, once done.
    6. apply filters prior to saving the output file

    7. The status of the saving process can be viewed with the help of the progress bar. The user can anytime terminate the process by clicking on the Stop button.
    8. clicking on the Stop button

    9. In the end, you will get a popup message stating the filepath of the recovered data.
    10. you will get a popup message stating the filepath of the recovered data

    Converting an OST file to a PST format is required in several circumstances, all of which are discussed briefly in this post. Due to the availability of many software tools in the data recovery market, the user might get confused. Hence selecting the right tool is also critical. Recoveryfix is a trusted brand and a leader in the data recovery segment. Therefore, we highly recommend Recoveryfix for OST to PST converter tool in situations when your OST file becomes inaccessible.

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