2019 visiting this looking for the solution of these "quan" things and it seems still dead end.. I experiencing this problem since i input the item that are not exist in inventoria.. since that the quan message always appear and cooper wont sync again with inventoria..
First i do backup all the copper data, then I try to re install copper and start over agaIn and re sync with inventoria then the problem are solved.. But the transaction data are lost. So i try to restore the from the backup data, the transaction are exist but the quan message appear again.
SO MY TIPS IS