This happens when there’s no application in Web Connector and you selected Select All.

What you can do

If you haven’t yet, connect your application:

Prepare your application's .QWC file. You need this for installation. If you don't have this, you can get it from your application provider.

Add your application in Web Connector.

Note: If you still get this error, reach out to Intuit Support.

Reference: https://quickbooks.intuit.com/learn-support/en-us/set-up-payments/fix-common-web-connector-errors/00/203305