Thought I solved the problem after re-installing. However the problem came back after a few days. Strange but true.

After setting up the printer, I added some applications and a few days later, I could not print again. Got the same error described in the following thread:-

http://www.knoppix.net/forum/viewtop...ghlight=cupsys

I think Knoppix 5 got a major problem with cupsys. It causing me some embarassment. Might have to revert back to Knoppix 4.