wireless keeps dropping, have to keep re-adding it to my network every few days

Diagnosis

The Brother DCP-L2640DW frequently loses its wireless connection due to "IP Address Drift." By default, the printer is set to DHCP (Dynamic Host Configuration Protocol), meaning your router assigns it a temporary IP address for a set period (the lease time). When that lease expires, the router may assign the printer a new IP address. If your computer or mobile device is still trying to send print jobs to the old IP address, the connection appears "broken," and the printer seems to have dropped off the network. This issue is exacerbated in environments with many smart devices or if the router is configured with a short lease window (e.g., 24 hours). You can confirm this is the problem by printing a Network Configuration Report from the printer's menu. If the IP address listed on the report differs from the one shown in your computer's printer properties or the Brother iPrint&Scan app, the printer has drifted, necessitating a manual re-addition to the network.

How to Fix It

To permanently solve this, you must assign a Static IP address to the printer. This ensures the printer always occupies the same "slot" on your network, preventing the communication break.

1. Print the Network Configuration Report: Press Menu > Print Reports > Network Config. Note the current IP Address (e.g., 192.168.1.15) and the MAC Address.
2. Access your router's administration panel via a web browser (typically 192.168.0.1 or 192.168.1.1).
3. Navigate to the LAN Settings or DHCP Server section. Look for a feature labeled Address Reservation, Static IP Assignment, or DHCP Reservation.
4. Click Add New. Enter the printer's MAC address and the specific IP address you want it to hold (it is best to use the one currently assigned to the printer to avoid conflicts).
5. Save the settings and restart your router.
6. On the printer's physical control panel, go to Menu > Network > TCP/IP > IP Address. Change the setting from Auto to Manual.
7. Enter the exact IP address you reserved in the router settings. Confirm the Subnet Mask (usually 255.255.255.0) and Gateway (usually your router's IP) are correct.
8. Press OK to save and restart the printer.

If That Didn't Work

• Disable 5GHz Band Steering: The DCP-L2640DW operates on a 2.4GHz frequency. If your router uses "Smart Connect" or "Band Steering" to merge 2.4GHz and 5GHz into one SSID, the printer may struggle to maintain a handshake. Create a separate Guest Network or a dedicated 2.4GHz SSID specifically for your printer and IoT devices.
• Change Wireless Channel: Interference from neighboring Wi-Fi networks or microwaves can cause drops. Log into your router and change the 2.4GHz channel from "Auto" to a fixed channel—specifically 1, 6, or 11—which are the most stable non-overlapping channels.
• Update Firmware via USB: If the wireless connection is too unstable to update over the air, download the latest firmware update from the Brother support site to a PC and connect the printer via a USB cable. Outdated firmware often contains bugs related to WPA3 security handshakes that cause intermittent disconnects.
• Adjust Power Management: Ensure the printer is not in a "Deep Sleep" mode that disables the wireless card. Go to Menu > General Setup > Interface and ensure the network interface is set to active, or adjust the Sleep Timer to a longer duration.

Heads Up

• Avoid placing the printer directly next to a wireless router or a large metal filing cabinet, as this can create signal "dead zones" or electronic interference.
• If you change your router or ISP, you must reset the network settings on the printer by going to Menu > Network > Network Reset before attempting to reconnect.
• Always use the "Full Driver & Software Package" rather than the basic Windows Class Driver to ensure you have the full diagnostic tools for monitoring connection status.
• Periodically check for "IP Conflicts" if you add new devices to your home; if two devices are accidentally assigned the same static IP, both will lose connectivity.