Import contacts to your address book in Outlook, formerly Hotmail, from a CSV file, a PST file or from another email service or app. While PST files only hold contacts from Outlook 2013 or Outlook 2016, CSV files can hold contacts from any email service.
To import contacts from a PST file to Outlook 2013 or Outlook 2016, click File, go to Open & Export, and click Open Outlook Data File. Browse for the PST file, select it, and click OK. Next, click on the People icon, navigate to My Contacts, and click the PST file you just opened. Click on the contacts list, select all the contacts, and drag them to the contacts folder.
To import Gmail contacts to an Outlook account, first log in to the Outlook account, navigate to Add People To Your Contact List, click Google Contacts, and then click Connect. Next, sign in to the Gmail account, click Allow Access, and click Done.
To import contacts from a CSV file to an Outlook account, log in to the Outlook account, navigate to Add People To Your Contact List, click Import From File, and then click Microsoft Outlook (using CSV). Browse for the CSV file, select it, and click Open. Next, click Import Contacts, click Look For Duplicate Contacts, and uncheck the row for any contacts you wish to keep separately. Afterwards, click Save.