MS Outlook, in the offline (Cached Exchange) mode, saves all the Exchange Emails with all types’ Mails folders/files items in a local file named OST file. The changes ready by the operator in the offline mode are later updated to the server mailbox items when the Exchange connection is re-established. As the outlook offline OST file resides on the user’s system, it is unaffected by Exchange Server crashes and disasters, Exchange mailbox deletions, etc. So, Exchange administrators and end-users can use OST files to restore user mailbox data in the occasions of such eventualities.

You can Use Manual Method-:

Export OST to PST file- Login to Outlook with the Exchange account that was used to create the unique OST files. And to export the offline OST mailboxes to PST, follow the simple procedure:  But this method is too risky for converting data from offline OST file to PST file, so I suggest you better & easy solution you can simply use third- party tool to Convert Offline OST to New Outlook PST file.

* You can quickly try third-party tool, although online market available lots of tools, which export OST file to PST format, But You can Search most popular solution name of KDETools OST to PST Converter software that has advanced feature to Convert OST to PST with you can according to save data from multiple formats-: PST, Gmail, Drive, Zimbra, office 365, Live Exchange, EMLX, MSG, vCard/vCal ( contacts -calendar ), HTML,  and MBOX etc. This tool easily recovers corrupt offline OST file emails and Convert OST to PST without Exchange profile or server connectivity.

KDETools for Outlook OST to PST is professional software which can freely convert 25 items from each OST folder to PST. Its advantage is that it can convert offline OST files to PST without an Exchange profile or Exchange Server connectivity. It has a highly user-friendly interface which lets the user select OST file(s), recover all items of offline OST including deleted emails, and Convert OST to PST format. Also, it can convert inaccessible OST files to PST at a time. Let’s see the working of the tool: This software works on all supported MS Outlook Versions-: 2019, 2016.2013, 2010 and 2007.

Convert Offline OST to New Outlook PST file

  • Recover corrupt ost file/emails
  • Solve errors issues of Offline OST
  • Converts Outlook PST to Gmail, Drive, Zimbra, office 365, Live Exchange, MBOX, EML, EMLX, MSG, HTML, and etc.
  • Export items from OST2PST with Mails, Contacts, Calendar, Tasks, Journal, etc.
  • Perform safe and complete conversion without data loss.
  • Easily split large PST file( 25GB)
  • Supported MS Outlook Versions-: 2019, 2016.2013, 2010 and 2007.
  • Easily works on all Windows versions-: 2016, 2013, 2010 etc OS.

Read More-: How to Export OST to PST