I'm useing windows 2000 pro w/microsoft office 2000 and a Canon pixma MP170 printer. My problem is after first starting the computer it will print fine but after a couple of hours it won't print. I had it in for repair and they cleared the hard DRIVE and reinstalled the operating system. It STILL does the same thing. It shows that its comunicateing with the printer but does'nt print. I hooked the printer to my laptop w/windows XP and have no problem printing. Any sugestions? Check your power saver settings. Look if the printer can be shut down by windows to save power. I know some network cards can be shut down and when you go to use them they don't always start BACKUP. Maybe your printer is doing the same.

You may NEED to update your printer driver, as well.are using a network or a standalone?I think "Spoiler" may be on to something... Lifted quote from following link:

http://techrepublic.com.com/5208-11184-0.html?forumID=49&threadID=173254&messageID=1763568

"
Check Power MANAGEMENT properties of USB Root H...
Check Power Management properties of USB Root Hubs in Device Manager. If "Allow the Computer to Turn Off This Device to Save Power" is enabled (check mark in box), disable it.

Power saving can cause connected devices to stop responding after it powers down hub and only remedy is a reboot.
"

I'm assuming this is a USB printer.