Why am I unable to send invoices? Keep getting delivery error showing.

Hello there, martinhercyk.

I'm here to help why you keep getting delivery errors when sending invoices, and I'll help you fix it.

There are two possibilities as to why invoices are undelivered. These are:

• It might be that the email address was entered incorrectly.
• There's a temporary issue with the recipient's email server.

With that, let's ensure that the details are correct. If they're correct, I'd suggest confirming with the recipient if there are any issues with their email provider. This is to verify if their system blocked any incoming emails from QBO.

If everything is fine on their end, you can perform some troubleshooting steps to isolate the issue further. To begin with, let's send invoices through an incognito window. You can use these keyboard shortcuts to open one:

• Google Chrome: Ctrl + Shift + N
• Microsoft Edge & Mozilla Firefox: Ctrl + Shift + P
• Safari: Control + Option + P

If it works, you can browse regularly and clear its cache. Piled browsing history can also be the reason for some errors when sending invoices. You can also use a different browser like Google Chrome, Mozilla Firefox, Microsoft Edge, or Safari to rectify the issue further.

Just in case you want to personalize your sales forms to reflect more of your business identity, customizing the template you use in QBO is a breeze. Here's an article to know more: Customise sales forms.

I'm always around whenever you need help with sending invoices.