Troubleshooting

My device isn't recognized during flashing—what should I do?

Common causes:

• Wrong USB cable: Many cables can only charge the device but cannot transfer data. Use a high-quality USB-C data cable.
• Missing drivers: Some devices require a CP2102 or CH340 USB-to-serial driver. Check Device Manager (Windows) or dmesg (Linux).
• Browser does not support WebSerial: The Web Flasher requires a Chromium-based browser (Chrome, Edge, Brave). Firefox and Safari do not work.
• DFU mode not enabled: For nRF-based devices (RAK4631, XIAO nRF52840), DFU mode must first be enabled—there is a "Enter DFU mode" button in Web Flasher for this purpose.

I don’t see any other participants—why is that?

• LoRa parameters are incorrect: The frequency, bandwidth, spread factor, and coding rate must match exactly. In Saxony: 869.618 MHz, 62.5 kHz, SF 8, CR 8.
• No repeater within range: Without a repeater, you’ll need another Companion device within direct radio range. Check the map for repeaters near you.
• Bluetooth connection interrupted: The app displays the connection status in the top right corner. If you encounter problems: Turn Bluetooth off and on, restart the app, or re-pair the device.
• Antenna not connected: It sounds trivial, but it’s a common source of errors, especially with devices that have an SMA connector. Without an antenna, the range is limited to just a few meters.

My repeater has issues with the time

An incorrect time can lead to problems with flood ads. The simplest solution: Connect to the repeater via the MeshCore app (Remote Admin) and synchronize the time. For RAK-based devices, an external RTC module is recommended, which retains the time even during a power outage.