Thanks for joining this thread, Ptaylor1.

Aside from making Outlook MS365 as the default address in QuickBooks, you also need to set this up to your email service provider.

I recommend consulting your provider so they can help change the default email account when sending an email. Once done, make sure to close and re-open QuickBooks for changes to take effect.

You can refer to this article, Connect your email for instructions and detailed steps. It includes what Internet Service Provider (ISP) to enter depending on your server.

I've also added the What’s new in QuickBooks Desktop 2020 link to check out the latest features and improvements in the system.

Keep me posted if you have follow-up questions. I'm here to help you succeed.