Let me help you fix this in no time, @Susanlynnmiller.

The error you received can be caused by a conflict between QuickBooks 2020 and 2021. We can fix this by updating your QuickBooks to its latest release of 2021.

Here's how: 

1. Close your company files and QuickBooks.
2. Open the Windows Start menu.
3. Look for QuickBooks Desktop, and then right-click the icon and choose Run as administrator.
4. On the No Company Open screen, go to the Help menu and select Update QuickBooks Desktop.
5. Select the Options tab and then choose Mark All, after click Save.
6. Go to the Update Now tab and click the Reset Update checkbox.
7. Once you're ready, choose to Get Updates.

When the update is finished, close and reopen QuickBooks Desktop. Then, click Yes to complete the process. Once done, restart your computer.

I've also added this reference you can read for further guidance: Use the Accountant's Copy

That should get you going in the right direction. Please let me know how it goes by leaving a comment on this thread. I'm here to help you always. Have a nice day ahead.