If you go to the top of the board you would like to add him to, click on the 'Invite' button, put in his email address and click 'Invite' and it'll send him another invitation! If he hasn't confirmed his email address for Trello, it'll tell you there!
Hope that's helpful!
Hello Community! My name is Brittany Joiner and I am a Trello enthusiast and Atlassian Community Leader. I'll be sharing with you a series of videos with my top tips on how to best use Trello...
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