After install cups and remove cups, my redhat 7.3 (2.4.20) never print
again. The lpq will show:

Printer: pr3@dhcp212
Queue: no printable jobs in queue
Server: no server active
Status: job 'nick@dhcp212+631' removed at 11:32:57.687
Rank Owner/ID Class Job Files Size Time
done nick@dhcp210+680 A 680 (STDIN) 191263

But windows machine print well.

How to trace this problem? I tried to change to unix print to jetdirect,
both doesn't work (it works before).