You can import contact lists and address books that are saved in a comma-separated (.csv) text file format. Import is available from your Import/Export Preferences
You can import contact lists that are saved in a comma-separated (.csv) text file format.
- Go to Preferences>Import/Export.
- In the Import section File field, browse to locate the contact .csv file to import.
- Select the type of contact file that is being imported. If you are not sure, select Auto-Detect.
- Windows Live Contacts
- Outlook contacts
- Account contacts. This is a contact list from a Zimbra account.
- Thunderbird contacts
- Outlook 2003 contacts
- Yahoo! contacts
Contact lists from different accounts may not display contact information in the same order. Picking the correct type of contact file that is being imported identifies the order of the fields so that the information displays correctly in your Address Book.
- Select the destination for this file. Select an existing address book to add the contacts or create a new address book to import the file. Click OK.
- Click Import.
- Click OK.
Source : zimbra.com