I've Googled the problem and tried every solution I found. Nothing's worked so far.
Printer: HP Color Laserjet 3600n, connected via Ethernet.
Problem: Every time someone on the network prints something, the internet access is temporarily cut. All devices on the network are affected. The devices still show that they are connected to the network, they just won't be able to load anything (downloads that are in progress get interrupted as well). The loss of internet access is very brief, maybe ~5 seconds. Again, the devices still show that they are connected.
1. Someone suggested that the printer may be taking too much power. My printer and router are now in different wall sockets and the issue is still here.
2. Someone suggested that the printer may be trying to "steal" an IP from another device. I've manually set the Printer's IP to "192.168.1.101". My other devices only go up to about "192.168.1.20".