OST to PST Converter

This tool converts inaccessible OST files to Outlook PST files. You can also use this tool to export or backup email, contacts, and calendar to an Outlook .pst file in case of data loss on mail server or when you need to recover deleted, orphaned or inaccessible .ost file.

Most of the data stored in Offline Outlook Data Files (.ost) remains on the server; however, any items that are saved locally should be backed up. For example, Calendar, Contacts, Tasks, and any folders marked Local only. You should periodically backup all of your email, contacts, and calendar to a safe place. After you convert ost to pst file format, copy the .pst file to a safe location: a USB flash drive, another hard drive, or cloud storage.

Open or export items from an offline Outlook Data File (.ost)

When an OST file can be opened in Microsoft Outlook, you can use it to export items by creating a PST file. If you're using Cached Exchange Mode, Outlook will only export the items in your current cache. By default, Outlook configures Exchange and Microsoft 365 accounts to only synchronize 12 months of your email. Follow the export instructions to move your email from the OST file to a PST file. To export more than the past 12 months of data, turn off Cached Exchange Mode first.

If you have Outlook connection issues with mailbox on a server or cannot open your OST file, use PST OST Viewer to open and export items from your OST file.

How to convert OST to PST file?

Follow this steps to export or backup email items from an OST file, including damaged, orphaned or inaccessible .ost files:

1. Close Microsoft Outlook and all other mail-enabled applications that may use your Outlook mailbox.
2. Download the OST to PST Converter, and run it on your computer.
   Download Installer (.exe) Download Portable (.zip)
3. Browse the OST file you want to convert and click Open.
4. Select the destination folder for PST file and click Convert.
   
5. Wait for the export to finish.

How to export deleted items from OST file?

Follow this steps to export deleted items from the mailbox:

1. Close Microsoft Outlook and all other mail-enabled applications that may use your Outlook mailbox.
2. Download the PST OST Viewer, and run it on your computer.
   Download Installer (.exe) Download Portable (.zip)
3. Browse the OST file you want to convert and click Open.
4. Preview all your items including email messages, calendar, contact, and task data..
   
5. Select All Hard Deleted items folder in All Folders pane, and go to File > Export.
6. Choose PST - Outlook Data File as file format and All items in this folder and subfolders.
   
7. Select destination folder and click Ok.
8. Wait for the export to finish.

After your email data is exported to a PST file, it's portable! You can save the .pst file to a portable drive; then open it with OST PST Viewer.

What data is exported?

• When OST to PST Converter exports email, contacts, and calendar info to a .pst, it makes a copy of the information. Nothing leaves .ost file. You'll still see and have access to your email, contacts, and calendar in .ost file.
• When tool exports emails, it includes any attachments to the emails.
• OST to PST Converter does not export meta-data such as folder properties (views, permissions, and AutoArchive settings), message rules, and blocked senders lists.

Online services to convert OST to PST

OST files contain your important and confidential data. When you use an online service to convert email from OST to PST, all of your sensitive data, including private messages, contacts, tasks and notes, is transferred to someone else's server. The data is processed on an unknown computer and you have no control over it. Only then will you be able to download the resulting PST file.

Are there any limits when converting from OST to PST?

There is no limit on the number and size of the converted OST files and the resulting PST files. You can convert unlimited files as often as you like.