Step 1. Turn on the 2-step Verification
Open your Google Account and click the Security tab. Activate 2-step verification if it's not yet enabled.
After 2-step verification is enabled click the App Passwords:
Step 2. Generate the App Password
Select Other in the dropdown.
Then specify the app name. It can be anything
Now you can copy the app password
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Step 3. Configure TrackMage
After you set up GMAIL go to TrackMage, open the team settings, and add new SMTP credentials like this: