Hello, @Htank910. We truly appreciate your efforts in performing troubleshooting steps and exploring workarounds to send your invoice forms. Allow me to share some important information below.
Please note that QuickBooks Enterprise Desktop 2021 was discontinued on May 31, 2024. As part of this policy, you will no longer have the option to send forms or reports directly through the software.
For more details, feel free to read this article. This is a 2023 version, but it applies the same rules: QuickBooks Desktop 2023 service discontinuation policy.
If you wish to achieve this, I recommend upgrading your QuickBooks Desktop to the latest year available.
In the meantime, you can download the invoice form as a PDF file and manually send it to your customer using your personal email account.
If you have any additional questions, please don't hesitate to reach out. We're here to assist you promptly.