How can I tell if an estimate or invoice emailed to a customer has not gone through?

Hi there, 

Congrats on your first post in the Community! QuickBooks offers a versatile platform that simplifies the way you manage your invoices and estimates. I'll be happy to point you in the right direction so you can continue to do the things you love. 

The program makes it easy for you to check the status of an estimate/invoice using the steps below: 

1. Click on Sales on the left navigation menu.
2. Select Invoices.
3. Under the Status drop-down, Select the status of your choice.
4. You'll be able to view the transactions with the chosen status.

Using the info you see on the status, you'll be able to determine whether the invoice/estimate has gone through or not. Based on the status, you can determine what to do next. 

Let me know if this info helps, I'll be a message away in case you need anything else. 

Thank you for the quick reply.

This is helpful with invoices, but I am not clear how this works for estimates?

You're welcome. You can check the status of your estimates by filtering Estimates on the All Sales tab. Here's how: 

1. Go to Sales then All Sales.
2. Select the Filter ▼ dropdown.
3. In the Type dropdown, select Estimates.
4. Select the date range from the Date dropdown.
5. Select the customers you want to see statements for from the Customer dropdown.
6. Select Apply.

From here you'll be able to see the status of the estimates as well. Here are some helpful  tutorials/webinars you can check out for tips and tricks on using the program. Let me know if you have questions, I got your back.