QuickBooks is unable to complete this operation

How do I duplicate this error?

You have two company files. You have company B open, but you are trying to sync with company A. You lack permission to sync with company A.

How do I resolve this error?

Here are the steps:

1. Right click QuickBooks.
2. Select run as administrator.
3. Login as admin to your company file.
4. Go to edit and click preferences.
5. To the left of Connex, ensure allow access is checked.
6. Click properties.
7. Ensure Connex Connex can login, even if the file is closed: 
8. Press F2.
9. Ensure the file path in Connex and QuickBooks is identical.
10. In Windows, search for Web Connector.
11. Right click the icon and select run as administator.
12. Check the box to the left of Connex and run the web connector.