I appreciate all the efforts that you've exhausted just to get this working, 112020.
I can share another set of troubleshooting steps that will fix this issue. Some users were able to send their invoices by separating the email address using a semicolon without space.
If you've already tried it, you can update your QuickBooks Desktop to the latest release so you'll so you won't miss our security patches and updates. Here's how:
- Select Help from the top menu bar.
- Choose Update QuickBooks Desktop.
- Go to the Options tab, then select Mark All and then select Save.
- Head to the Update Now tab and tick the Reset Update checkbox.
- When you're ready, click Get Updates.
However, if you're still unable to send the invoices, I'd recommend running the built-in repair tool. It could be that some components of the program are damaged causing email delivery issues.
Additionally, here are some articles that you can read to help resolve common emailing issues and errors in QuickBooks Desktop:
I'll be right here to continue helping if you have any other concerns or questions. Assistance is just a post away.
