TNAS and your computer are not on the same network segment. Please connect both on the same subnet.
Windows Defender has blocked TNAS PC. Follow the instructions to prevent this from happening.
Your computer or router has a firewall, and so you should turn off the firewall and try again.
Your computer is using a network proxy connection. Please disconnect the proxy connection and try again.
The hard drives you installed may have been used on other devices. Please turn off your device, remove all hard drives, turn on the device and try again.