Reduce the size of your mailbox and Outlook Data Files (.pst and .ost
https://support.microsoft.com/en-us/office/reduce-the-size-of-your-mailbox-and-outlook-data-files-pst-and-ost-e4c6a4f1-d39c-47dc-a4fa-abe96dc8c7ef
WebIf you use an Microsoft 365, Exchange, IMAP, or Outlook.com account, a copy of your mailbox is stored in an Offline Outlook Data File (.ost). To reduce the size of your Outlook Data File (.pst) or Offline Outlook Data File (.ost), you can manually compact the data file.
DA: 76 PA: 90 MOZ Rank: 4 Up or Down: Up