When you sign up for an IMAP account and you have an IMAP account, your Outlook data is stored in a pst file, an ost-file, or a combination of the two. This can make it difficult to backup your email and other data like Calendar, Contacts as well as Tasks, for IMAP accounts.

Your email folders and emails are saved within your IMAP server and synced to Outlook which saves them to an internal caching file in your personal computer.

  • Outlook 2007 as well as Outlook 2010 Your mailbox cache is located inside the PST-file.
  • Outlook 2013, Outlook 2016, Outlook 2019, Outlook 2021, and Office 365
    The cache of your mails is kept in an the ost-file.

You can find the location and the name of the pst or file using the article: How to manage pst-files.

Your other information (Contacts and Calendars, Tasks, Contacts and Notes) are not saved on and synced with your IMAP mail server because the IMAP protocol can only synch emails.

  • Outlook 2007 and Outlook 2010
    Your Calendar, Contacts Notes, Tasks and Contacts are kept in an extra pst-file.
  • Outlook 2013, Outlook 2016, Outlook 2019, Outlook 2021, and Office 365
    Your Calendar, Contacts Notes, Tasks, and Contacts are stored within the same ost-file however Outlook is able to save this information in an additional pst-file (recommended).

Related blogs:

Import PST to Thunderbird

Import PST to Gmail

Email Gmail emails


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