If you receive the error similar to the one below:
Invoice : I010921 ERROR - There is an invalid reference to QuickBooks Customer "APPLE LOGISTICS" in the Invoice. QuickBooks error message: The specified name is either invalid or of the wrong type.
It means that there is already an existing Vendor in Quickbooks that has the same linked account name as Customers AR account. Either change the customer's Linked Account AR code in Fleet Manager or rename the Vendor Name in Quickbooks. A Vendor and Customer cannot have the same name in Quickbooks.