CRM is not sending out emails
When sending out emails via your CRM, it will use whatever email client is your default on your browser. Therefore you have to make sure whatever email you usually use is set up as your default or you'll receive an error.
For example if you use gmail, but your default is outlook, then you'll have to change your default to gmail. Unfortunately as members have and use many different browsers, operating systems and email clients, you would have to google which ever one applies to you, ie "how to make gmail my default email client".
There is additional training under the Marketing Strategies as well as details for setting up your default email client.