The cartridges were changed ganau to enclosed instructions. Result - the black cartridge has but partially not working, ie photo print took place including black ink, document printing did not work (Journal was unprinted ejected).. Printer polls were made - from the printer no error was displayed, the ink level inquiry also revealed the correct result (full). Support by seller was very good - but errors could not be corrected even after several tips and instructions of the seller. 47, Hab after all the hard work Original cartridges to Euro - ordered free shipping, these are working properly and are, at least as regards my printer is an Epson WF 3520, the better solution. Now I should pay my asking the seller with regard to the Conditions of return itself. Already at a value of 20 euros, paid 10 euros shipping. Now the same thing again - not with me - absolute no-go. Would discourage any order!