There is an invalid reference to a parent *.* in the Bills list. Quickbooks error message: Invalid argument. The specified record does not exist in the list.

If you receive this error and you are using the Canadian/UK versions, then in QB, open the Sales Tax Code list, create the new tax code only using the period symbol ( . ) and save. Do a Selective Sync in AO. You will now have a ( . ) in AO Sales Tax Codes list. The error should be fixed.