the printer was bought two years ago. It worked fine until last month. the error message says "The appropriate print head is not installed." I sent a message to canon's service department, the response is to buy a new print head. I never did any inside cleaning or maintenance except refilling the ink cartridges. the pritner is kept clean. the questions are: any solution to fix this error? should I order a new print head? may it be any other problems besides the print head?