To back up your Outlook contacts, you can export them as a .pst file or a .csv file:
.pst file
Select File
Select Open & Export
Select Import/Export
Select Export to a file
Select Outlook Data File (.pst)
Select Contacts
Choose a location and name for your backup file
Select Finish
.csv file
Select File
Select Open & Export
Select Import/Export
Select Export to a file
Select Comma Separated Values
Select Contacts under the email account you want to export contacts from
Select Browse and go to where you want to save your file
Type in a file name and then select OK
Select Finish
