Can you post the output of
sudo lsof -i :631
Is there anything else than cupsd listed? Can you kill all the listed processes, check whether no new processes come up and then start CUPS with
sudo /etc/init.d/cups start
Does CUPS start up, are you able to print?
Does CUPS start up again when you reboot? If not, do
and post the output here.
Can you post the output of
sudo lsof -i :631
Is there anything else than cupsd listed? Can you kill all the listed processes, check whether no new processes come up and then start CUPS with
sudo /etc/init.d/cups start
Does CUPS start up, are you able to print?
Does CUPS start up again when you reboot? If not, do
sudo lsof -i :631
and post the output here.