Hello @Gazbo ,

Welcome to our community.

As I know, the Archer MR600 V2, like other 3G/4G/5G LTE routers, cannot function as a repeater or range extender. It does not support WDS (Wireless Distribution System) for connecting to an existing Wi-Fi network wirelessly. The LTE router is designed to connect to the internet directly via a SIM card or through an Ethernet cable, but it cannot wirelessly extend another router's WiFi signal.

May I know your exact network topology? For example, Starlink device—MR600)))((( client devices

(Note: — stands for wired connection,)))((( stands for wireless connection )

Here are some troubleshooting Steps that you can try:

1. Verify All Devices Are on the Same Network: Make sure your laptop, iPhone, Smart TV, and NAS are all connected to the same WiFi network. 
2. Check Guest Network Settings: If you're using a guest network on either the Starlink or MR600, ensure that "Allow Guests to See Each Other" and "Allow Guests to Access My Local Network" are both enabled.
3. Verify IP Addresses and Subnet: Check the IP addresses of your devices to ensure they're all in the same subnet. You can refer to this guide: How to find IP address on your devices
4. Test Network Profile (for Windows devices): If using a Windows laptop, change the Network Profile following this guide: What should I do if I cannot access printer/internal server after changing the router
5. Ping Test: Try pinging the IP address of your NAS from your laptop to verify connectivity. Instructions here: How to use the Ping command