I have a large format printer (signs, vehicle wraps, etc.) that prints fine when connected directly to the wired (ethernet) port with a manual static IP (192.168.1.49) connection however my Internet browser can't load webpages. If I change the wired connection to DHCP or change the subnet to something other than what the local wireless router uses, the wireless connection immediately starts to work but the printer no longer works.
This setup has worked before, and it works with a local Windows 8.1 laptop. It's the main Windows XP SP3 desktop PC that can't make both connections work simultaneously anymore. This PC was infected with malware and Trojan horses. I have cleaned all that out since the printing issue occurred.
Am I missing something obvious with my setup? Could the issue be due to missing or corrupted networking software on the Windows XP desktop? Is there a way to fix the networking software without a Windows reinstallation such as a reinstallation of network drivers, etc.?
(The wireless connection uses a DHCP IP assigned address of 192.168.1.84 with a USB wireless adapter, and the wired connection works fine when using a static IP of 192.168.1.49. If I change the wired connection to DHCP or static IP, e.g. 192.168.2.x, the internet starts to work but the printer doesn't. I've read that some OS's don't gracefully use two NICs with the same subnet.)
Any help is much appreciated, Thanks!