I can provide some insights on how you can save the message in your email invoice, Bonnie.

You'll want to ensure your QuickBooks Desktop (QBDT) is updated to the latest release. This will install the newest features and fixes. Let me show you how.

1. Go to the Help menu and select Update QuickBooks Desktop.
2. Select the Update Now tab.
3. Click Get Updates to start the download.
4. When the download finishes, restart QuickBooks.
5. Then accept the option to install the new release.

You can also check this article for more details: Update QuickBooks Desktop to the latest release.

If the issue remains, I recommend running the Verify Rebuild tool. This scans your company file for errors and quickly fixes them.

I've also added these links that provide detailed steps on how you can personalize your sales forms and record invoice payments: 

• Use and customize form templates
• Record an invoice payment

Let me know in your reply if you have other follow-up questions about emailing your invoices. I'll be around ready to help you. Keep safe!