Is your loopback interface configured? The start output of 'ifconfig lo' should look something like:
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
The important bit is the "UP" keyword. If that's not the problem, please try: 'sudo netstat -lpn | grep 631' and post the output here.
Is your loopback interface configured? The start output of 'ifconfig lo' should look something like:
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
The important bit is the "UP" keyword. If that's not the problem, please try: 'sudo netstat -lpn | grep 631' and post the output here.