Gmail accounts will require 2-Step Verification (2SV) set up and an App Password generated in order for the Mail Tracker to successfully connect with a Gmail mailbox.
From the Google Account, select the account Icon (top right-hand-side)
Select Manage your Google Account, then Security, then Signing in to Google section
Ensure 2SV is set up and turned on
Once 2SV is set-up the App Passwords option will then be available
Click App Passwords option and confirm mailbox password
Select app option then Other (Custom Name) > Enter Reference for 3rd party app, eg. Gold-VisionCRM then click GENERATE
Copy the app password for use instead of the mailbox password when setting up the Mail Tracking Settings