Use your Cloudiance zMailCloud Zimbra webmail client to export and import data to make local backups of contacts, calendars and even your email.
Navigate to your Preferences > Import / Export
Chose which folders (e.g.: Contacts, Emailed Contacts, etc.), Account, and Advanced Settings to select which data you'd like to save, and enter the date range you'd like to save (if applicable).
Include the metadata if you'd like to be able to re-import into your Cloudiance zMailCloud account, or another one, at a future date.
Note that you may also export into various standard formats such as .CSV and Outlook.
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Looking to make an Outlook backup file, but not using Outlook?
the backups produce a .tgz file, not a .PST file. If instead you want an Outlook backup file (.pst), one of our customers did some research and found this solution which worked for them:
https://www.nucleustechnologies.com/how-to/export-zimbra-to-pst-on-hard-drive.html
The actual tool: [ https://www.nucleustechnologies.com/imap-backup/