Definitive Guide: Factory Reset Brother HL-2170W Wireless Printer

http://binglongx.wordpress.com/2013/06/23/definitive-guide-factory-reset-brother-hl-2170w-wireless-printer/

The little printer was easy to set up initially, see a previous post. However, Brother does not have very good configuration support if anything changes in the wireless network, for example, your wireless router, SSID or key. Supposedly you just need to re-connect the Ethernet cable, and re-run Wireless Setup Wizard for Windows to let the printer know your new wireless network information, and restore printing. What you may often see, however, is that the Wizard reports it could not find the printer at all, letting alone allowing you to change its configuration.
The problem is that the printer is stuck with the stale network information and even prevents configuration connections. Whenever the PC cannot see the printer, the recommended approach is to factory reset the printer and redo the setup process. You can find the official factory reset instructions here. However, the instructions are too concise and do not tell you what is normal and what is not during the process, and you could wonder if you did it right. I stumbled a few times on that. By combining the official instructions with Brother HL-2170W: Installation Gotchas + Reset to Factory Settings and How do I configure the wireless printer with the temporary use of a network cable and install the printer driver in Windows, and after some experiments, I believe below is the best guide available over the internet for factory resetting Brother HL-2170W:

1. Turn off the printer.
2. Remove the Ethernet cable and USB cable from the printer.
3. Remove paper from printer and close the front cover. Removing paper is optional and to save paper and toner; if you go wrong, the printer may print TEST PRINT pages, which I have had a bunch…
4. Hold the Go button and turn on the printer. In fact the Go button is the only button that you can operate. It is white, and has blue light when on.
5. Keep the Go button pressed down until the Toner, Drum and Error LEDs light up. For my printer, as soon as I power up the printer all the three LEDs light on immediately.
6. Release the Go button and make sure the Toner, Drum and Error LEDs go off. Again, for my printer, the three LEDs go off right after I release the Go button. At this time, all the LEDs and the Go button light are off.
7. Press (and of course release) the Go button 7 times. When the Go button is pressed, its blue light is on. After 7 presses, all the LEDs and the Go button light are off. For a few seconds, the printer may not seem to respond to your presses at all. Don’t worry, I believe it is just unsure and waiting for you to press more if you want to do some other secret settings. For example, pressing Go more times can print the TEST PRINT page.
8. After the waiting period (for my printer this silence takes about 10 seconds), all the Toner, Drum and Error LEDs and the Go button light come on briefly and go off, then the Go button light slowly flashes for a few times. This means the factory reset is successful.
9. After the factory reset, as you usually see when the printer is turned on, it makes some noise and then the Go button remain lit. The printer is now ready.

If you believe you go wrong in the middle, just turn off the printer and start over. The procedure above could be too much for first time users. In my point of view, since any change in network settings essentially requires resetting the wireless printer, Brother could have really added a reset button in the back of the printer and made it painless.
Once your printer is reset, you can use an Ethernet cable to connect it to your home network. If your router has a DHCP server, HL-2170W will try to get an IP there. The instructions say that you may need to wait for 1 minute, but I can see that the printer gets an IP right away from my router in the router’s management page. It is also shown that the printer names itself as BRNxxxxxxxxxxxxxx in the DHCP client list.
Now you just need to run Wireless Setup Wizard for Windows, and it will see the printer with the BRNxxxxxxxxxxxxxx host name and IP from DHCP. You just need to follow the rest of Installing Brother HL-2170W Wireless Laser Printer to finish the installation.