I appreciate your time in sharing your concern with us, WindsorGardens.
The issue with invoice delivery errors can best be handled by our QuickBooks Care Team. They can look into your account and review the Sales settings to determine the cause of the this delivery errors.
To reach them:
- Go to the Help icon at the top to select the Contact Us link.
- Enter a brief description of your concern in the field box and click the Continue button to see the list of support options.
- Then choose Chat to start a conversation or Callback to speak with an agent.
I’m adding some links below for additional resources. These articles will guide you on how to troubleshoot email delivery issues. They’re from another region, but the solutions also apply to the UK version.
You can always visit the Community if you have additional concerns while emailing invoices. I’ll get back to make sure everything will be taken care of. Have a good one.