hi paul below is the configuration of squid.conf
# TAG: visible_hostname <==== this configuration is to be changed to the name of the PC? i've been editing still the same.
Yes, that's the one it's telling you to use. So you need a line like:
visible_hostname squid.example.com
Does that still not work?
What is the output of the "hostname" command on your comouter?
Paul.