I have three computers, 2 WinXP and 1 Slackware, coupled to a router for cable internet sharing. No problem here. All three boxes coupled to a HP printer with a manual switch. I have not done anything to set up a network. No problem here until I set up the Slack box for printing today.

As root, I did chmod +x/etc/rc.d/rc.cups, then /etc/rc.d/rc.cups start. Got on localhost:631 and went thru the procedure. All went well, the printer did a CUPS test page and I printed out some other stuff. Later, after rebooting the Slack box, it would no longer print. Neither would the Win box I was using. All the attempts to print were in the Win print queue and after clearing it the Win box would print; however the Slack box would not.

I notice that when rebooting the Slack box, a line comes up that says "dnsmsq:failed to bind listening socket for 192.168.1.102 address already in use." 192.168.1.102 is Slack box IP.

Being a Linux newbie, this has me totally confused. Since the Slack box did print, one time, I wonder if the problem is caused by using the switch rather than networking the computers.

If I understand you correctly, you're using a data switch?
And you switch it between computers? Perhaps when you switch
back to Slackware you're going to have to restart CUPS to
get back in touch with the printer? (/etc/rc.d/rc.cups restart)

You can issue "lpq" to show the printer queue status. If some
jobs are 'hung' use "lprm <ID>" to remove jobs from the queue.

Yes, using data switch.

lpq shows printer not ready. Restarted Cups (should have started at boot). lpq again shows printer not ready.

Welcome to LQ!

Sometimes I have this same issue, and have to enter
"localhost:631" in my web browser and start the printer
from there. For over 2 years I've had this experience,
from Slackware-9.1 to Slackware-current. Have not yet
found out the cause or any other solution.

Looks like we have the same problem. Got on localhost631, started the printer, and it printed a test page. Thanks for your help.