Hello can I know what's wrong when I send invoice I get error

Welcome to QuickBooks Community, ahmedelmongy023!

I'm here to help you figure out why you received an error when sending an invoice. Also, ensure you'll be able to send it without receiving an unusual message.

Before proceeding the possible some steps, I'd like to confirm the error message you got. This way, I can provide a solution to your concern in no time. You can also provide a screenshot. Make sure to cover the important details, like the email address.

In the meantime, make sure to enter an email address under the Customer email field. 

If you only want to save the transaction, use the Save button or utilize the other options by clicking the drop-down arrow, excluding Save and send.  Here's a sample screenshot for additional reference:

Also, let's perform some troubleshooting steps to let QuickBooks run smoothly when creating and sending transactions. Start by logging in to your account using a private or incognito window. This fixes unusual behaviors and errors in the program. These are the shortcut keys:

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

If that works, we can go back to your main browser and then clear the cache and cookies to get rid of the accumulated junk files. Switching to other supported web browsers can be a good alternative, too.

To manage your income and customer's data, feel free to visit this article: Topics about your company's income and customers.

Don't hesitate to post again if you need more help saving transactions in your book. I'm always here to back you up. Take care and stay safe.