I have a Canon iP 4500 which I am happy with except for one thing. On several occasions when trying to print an error dialogue appears saying an ink cartridge has not been recognised, normally the large black ink cartridge as the indicating light is off. To overcome this I have to remove the cartridge and reinsert it then it will be OK. Anyone any thoughts or remedy for this? XP sp2 fully updated as are printer drivers. Thanks in advance.