Device Not Detected

A lighting, cooling, or peripheral device you expect to see is missing from Nexus.

1. Close other control software. Most controllers accept only one connection at a time, so another app that drives the same device (including the manufacturer's own tool) can hold it before Nexus gets there. Nexus warns about this when it recognizes the running app: a Conflicting apps detected dialog lists the apps that drive the same lighting, fans, or peripherals as Nexus and lets you choose which ones Nexus terminates. Terminate what you do not need, then restart Nexus. See Other RGB & Fan Software.
2. Confirm the device is supported. In the dashboard, open the Devices page and click Supported Devices to search the catalog by brand or model; the list highlights devices detected on your system right now. You can also browse the same catalog on the devices page and in Supported Devices. If your device is not in the catalog, Nexus does not support it yet; request it on Discord.
3. Check the physical connection. On the Devices page, click Connected Devices to see every USB device currently attached to the PC, including devices without Nexus support. If your device is missing there too, the OS itself does not see it: reseat the cable, try another USB port, and prefer a port on the motherboard over an unpowered hub.
4. Restart the service. Windows: restart Nexus Service in Services (services.msc). Linux: sudo systemctl restart nexus. macOS: quit Nexus and launch it again. If a device was held by another app, a restart after closing that app is what lets Nexus claim it.
5. Reboot the PC. Some controllers only re-enumerate cleanly after a cold start, and a reboot also clears any app that was still holding the device.

If the device is in the supported catalog, shows under Connected Devices, and still never appears after a reboot, collect the log files and report it: Log Files & Reporting a Bug.