Archiving OST emails to PST file
Before starting the procedure in this solution, it is to be mentioned that users cannot move contacts or other mailbox items except emails to PST files through this method. Only emails can be archived to PST.
You need to enable archive in order to save OST emails to a new archive PST file. Also, the OST file needs to be accessed in the Outlook application, i.e. Exchange connection is needed. Perform the given steps to enable archive for an OST mailbox.
Open your Outlook application and then navigate to File>Options.
Now, click on the Advanced option. Under the AutoArchive feature section, click on AutoArchive Settings.
In the opened AutoArchive window, add values as per your need to AutoArchive frequency of days, the period for deletion of old items, etc. Here, under Move old items to section, you can browse and add the PST location where you want to save OST archived data. After all AutoArchive settings, click OK.
Hence, OST emails are archived to the PST format at your defined system location.
Note: This Archiving feature also helps in maintain Outlook file sizes by auto-archiving or deleting old items from the file by defined settings. You can also navigate to File>Info>Cleanup Tools>Archive to use the facility of manually moving old items as per the time filter from the OST file to Archive Folders in the PST list to a specified destination.
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