To troubleshoot Linksys Velop setup issues, first, ensure all cables are securely connected and the Velop nodes are powered on. Next, try power cycling the Velop system and restarting your modem. If the issue persists, reset the Velop nodes to factory settings and reconfigure them. Additionally, ensure your Velop system's firmware is up to date. Finally, consult the linksys velop troubleshooting guide or contact Linksys support for further assistance.