Printer Shutting Down On Wireless Network Using Network Magic Software

Before installing the latest version of the Network Magic software my printer was connected via USB to my computer running Windows XP. I am using a Linksys Wireless Router. I recently set up a new computer running Windows Vista in another room and wanted to network it wirelessly sharing the printer. I followed all the NM instructions and the printer was being recognized by the Vista computer but indicated it was offline and did not print. Thinking that it was a driver issue, I downloaded the latest drivers from HP but this did not help. On the HP website I read that I should connect the printer to my router using an Ethernet cable. Now the room that has the printer and XP computer has the printer connected with both the USB and Ethernet cables, Ethernet directly into the wireless router and the USB still to the computer. This enabled the Vista computer in the other room to work with the printer. I am able to see both computers and the printer on the NM Map online and ready to print. The issue that I am having now is that after awhile, maybe a half hour or so, the printer shuts down. Is it the connection, the NM software or a combination of both? Should I disconnect either the Ethernet or USB cable? I am happy that I am now able to share the printer, but it is annoying that I have to check to see that the printer in on before attempting to print something from the Vista computer in another room.

Unfortunately, I still have the problem, printer shutting down after about half an hour. Accessed HP online support and they advised several things to no avail. Print sharing only works when I have either the USB and Ethernet cables connected at the same time or if USB is connected without Ethernet to wireless router but not if Ethernet is connectly only. I think it is a software glitch or a Vista bug. I'll keep trying but at least I get print sharing even though I have to turn on the printer manually every so often.