E12 is a water fill time out error,in other words the water never got to a set level within the given time.it could also mean the inlet valve has failed
E21 is a blocked drain issue.You say you have checked the filter at the bottom right?.Remove the filter again and shine a torch in to the filter housing and check if anything is jamming the drain pump impellor.flick impellor round using a long screwdriver to make sure it rotates freely
Now put it back together and retest
ck
August 2010