DIAGNOSIS The printer's wireless setup is sensitive to network environment and signal strength. The most common cause is an incompatible security protocol or a 5GHz-only network.
FIX Use the WPS push-button method if your router supports it. Press and hold the printer's Wi-Fi button until the Wi-Fi LED flashes. Within 2 minutes, press the WPS button on your router. Wait for the Wi-Fi LED to stop flashing and stay lit.
IF THAT DIDN'T WORK The printer only supports 2.4GHz networks. Ensure your router's 2.4GHz band is enabled and broadcasting. Move the printer closer to the router, away from large metal objects or microwaves, and restart both the printer and router before trying setup again.
HEADS UP Network setup via the USB cable and Brother software is more reliable for complex networks. Use the 'Initial Wireless Setup' option in the Brother software installer if the front-panel method consistently fails.