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Open the Outlook Desktop Client.
Click on File > Add Account
Enter your gmail and click on connect
Enter your information and then click next
After logging your Gmail account into the outlook app you might need to restart the Outlook Desktop Client
After you have restarted the desktop client, click on File > Open & Export > Import/Export
On the Import and Export Wizard select Import from another program or file
On Select file type to import from, choose Outlook Data File(. pst).
On File to Import select the file you exported from your outlook account and in options choose Replace duplicates with items imported
On Select folder to import from, Select Outlook data file and choose Import Items into the same folder as your gmail.
This process is primarily used by those looking to move all of their university emails to an external account due to account deactivation when they graduate. This can be used to move all emails from their student email address to their alumni email address.