Version History

June 5, 20242.22.0038Major Update

This release includes several performance-related improvements. This release was also tested on latest versions of Windows 11 with Microsoft Outlook for Microsoft 365.

This release includes several performance-related improvements. The product was also tested on latest versions of Windows 11 with Microsoft Outlook for Microsoft 365.

Issues Fixed

  • OST2 process was not exiting properly and was preventing Outlook from opening in some cases.
  • Links on some dialogs were opening duplicate browser tabs.

July 14, 20222.20Major Update

This update introduces a new feature - an option to change Data file size before conversion

New Feature:

  • Increase maximum file size allowed by Microsoft Outlook. In case you are converting a huge file (50GB or larger), conversion would fail. By increasing the maximum file size, you can avoid failing conversions!

April 30, 20202.14Major Update

The hotfix resolves the issue where application would not start when the recent Microsoft Outlook update 2003 or 2004 would be installed.

Functional Changes:

  • Updated the error message in case product cannot be started;
  • Added a hyperlink to Outlook Toolbox website in case conversion process fails;

June 18, 20192.13Major Update

The new version of OST2 has improved OST files conversion process. Also, new feature - recover files from corrupted or unreadable folders. Try it today!


October 5, 20182.12Major Update

The updated version of OST2 will convert and transfer calendar events and tasks even with the latest 2018 Windows October Update.

September 14, 20182.11Major Update

The update includes a number of fixes reported by our customers.

Issues Fixed

OST2 Issues:

  • Conversion would get stuck after PST file reaches maximum allowed size. A new error will be shown when such situation occurs;
  • Application would close unexpectedly when converting specific file;
  • Files would fail to convert if application files are stored on a network drive;
  • Application was working incorrectly when architecture of the program would not match the system architecture;
  • Additional message has been added that is displayed if Outlook is installed, but no Outlook profile is setup when starting the application;
  • Other minor or cosmetic bug fixes.

February 28, 20182.10Major Update

The purpose of this update was to introduce new mode of conversion called “Recovery Mode” which is dedicated to get as much data as possible from source file. In addition to that, we fixed issues that were noticed by our customers, our support or quality assurance teams.

Functional Updates

    "Recovery Mode" of conversion for both orphaned and connected OST files. When using this mode in addition to usual conversion OST2 does the following:

  • Un-hides items that are hidden in each folder of original file when saving them to destination;
  • Recovers items from "Deleted Items" folder to a folder named "Recovered_Data" in destination data storage;
  • Gets "First Name", "Last Name" and "E-mail Address" information from each Calendar item if they are present and creates corresponding Contacts in the "Recovered_Data"/Contacts;

Issues Fixed

OST2 Issues:

  • Conversion would get stuck on 5% of progress and would not finish; Several cases are known when this could happen and they are now handled differently, corresponding error message is shown.
  • Items, converted from OST to PST file, were empty (Outlook 2003 only);
  • Filters would not work when transferring items from orphaned .PST file to new .PST file;
  • “No files connected to Outlook were found" message would be shown when "Scan Outlook..." button is clicked (only for “Fall Creators Update” Outlook 2016 x64);
  • PST file would not get created after conversion, error icon and "Conversion completed successfully" status is shown (only for “Fall Creators Update” Outlook 2016 x64);
  • OST2 would remove the prefix “\\?” in Outlook data files path, which would make conversion not to work;
  • Duplicates of default folders would be created in destination when converting orphaned IMAP “This computer only” folders;
  • User could deactivate OST2 if he made 2 orders and one of them is more than 2 weeks old;

June 15, 20172.00Major Update

The purpose of this update was to introduce completely redesigned OST2 Wizard like User Interface. By implementing this new Wizard, we wanted to put every user who downloads OST2 on right tracks straight away – offering right start for each use case from the Step 1 of OST2 Wizard right till the end.

Functional Updates

  • The improved Wizard - user can choose what is best for him and start Conversion, Migration or Transfer, follow simple Wizard and check the status of Conversion or Transfer in the last Step. Together with this, second goal was to seamlessly integrate OST PST Viewer and Safe PST Backup so that after conversion user has an option to either open file he just received or setup backup scenario (they still would have to download and install those tools).

Issues Fixed

OST2 Issues:

  • After activating OST2 you do not need to restart the tool for activation to take affect
  • Sometimes Contacts/Calendars/Notes were placed into wrong folder ("Drafts") in converted PST file, depending on orphaned OST file Outlook version

March 8, 20171.41Major Update

The purpose of this update was to optimize the performance of the tool and decrease time needed for the conversion. Several other issues fixed.

Functional Updates

  • The conversion process is now performed 30%-50% faster than before; Speed improvement varies depending on the items to be converted size and type;

Issues Fixed

OST2 Issues:

  • When converting, in case there was an item in the orphaned OST file over 5 MB in size, OST2 crashed;
  • Several other minor / cosmetic issues fixed;

January 20, 20171.40Major Update

In this version of OST2 the Free Edition limitations are expanded so now the users can convert 5 items in each folder of orphaned OST file. In addition, there will no longer be different installation files for the Free and Enterprise Editions of OST2. Several issues have been fixed as well.

Functional Updates

  • The Free Edition now converts the orphaned OST files as well, but only 5 items per folder.

Issues Fixed

OST2 Issues:

  • During the conversion, the status progress bar would disappear if you close and open the OST2 again;
  • Some minor user interface issues have been fixed.

October 23, 20161.30Major Update

This release has improved support of the latest OST file formats of Outlook 2016. It also offers several important fixes related to OST file scanning functionality and administration options.

Functional Updates

  • Improved support of the latest OST file formats. Some additional improvements have been made to support the latest OST file format of Outlook 2016.
  • German, French, Italian and Spanish languages are added.

Issues Fixed

OST2 Issues:

  • OST files could not be converted when Microsoft Outlook is installed, but not configured on the system (no Outlook profile created).
  • In some cases non-default OST file connected to Outlook could not be converted.
  • In some cases none or only one OST file was found during scanning, when multiple OST files were connected to current Outlook profile.
  • Application was always started with Windows start regardless of the setting in config file. Now by default application is not started automatically with Windows.>
  • In some cases file shown in the “OST file to convert” was not the one that was set in config file.
  • Next and last conversion time was not shown until the application is restarted.
  • Email notification to “AdminEmail” set up in config file was not sent when conversion failed
  • Parameter “Stop” to stop the current conversion process from command line was not working.
  • In some cases parameter “Start” to start the conversion process from command line was not working.
  • DestinationFolderCheckInterval” parameter settings were not applied after conversion failure when destination folder was not available.

June 22, 20161.20Major Update

This release offers support for latest Outlook 2013 and 2016 versions, and tested on Windows 10.

Functional Updates

  • Support of latest Microsoft Outlook 2016 and Windows 10. The product has been improved and fully tested with latest Microsoft Outlook 2016 and Windows 10.

October 1, 20141.12Major Update

This update adds the support of Outlook 2013 compressed OST files.

The support of Outlook 2013 compressed OST files has been added. Additional improvements have been made to improve the support of OST files, created using Exchange ActiveSync compatible services (such as Outlook 2013.

March 22, 20131.11.0136Major Update

This update offers several bug fixes reported by customers.

Issues Fixed
  • Enterprise edition needed to be restarted after activation.
  • In some cases it was not possible to open the “Open File” dialog if Outlook profile is corrupt.

July 6, 20121.10.0034Major Update

This update offers new functionality of converting any OST file unlinked to Outlook.

Functional Updates

  • Conversion of unlinked (standalone) OST files support. Now any OST file that is not linked to current Outlook profile can be converted to PST file (Enterprise edition only).

Issues Fixed

  • “SyncInterval” parameter in configuration file was not supported correctly.
  • “SkipNonLocalOSTs” parameter in configuration file was not supported correctly.
  • If several OST files were converted, and some conversions were not successful, the successful conversion status was still shown. Now a warning message appears in that case informing about the failed files.
  • Several issues fixed related to the command line parameters.

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I wasted half a day trying to find a free application to convert an OST file to a PST file. Believe me the free solution does not exist and my time was worth a lot more than the $50 I spend on..."
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