@Starboy2008 

Okay, I understand that you are experiencing issues with port forwarding on your Deco Mesh system after a recent firmware update. Specifically, the port forwarding rule you set up to a reserved IP and specific port works intermittently—it sometimes stops working, but resumes if you change the port and update the settings. You also mentioned that connecting your computer directly to the modem resolves the issue, indicating the Deco is likely blocking or closing the port unexpectedly.

To address this, please review the following steps for setting up port forwarding on your Deco Mesh:

Port Forwarding Setup:
1. In Router mode, open the Deco app and navigate to MORE > Advanced > NAT Forwarding > Port Forwarding.
2. Create a port forwarding entry for your device, specifying both the internal and external ports, and select the reserved IP address of your computer.
3. The Deco app will automatically create an address reservation for your selected device, ensuring it always receives the same IP address via DHCP. This is important because port forwarding may fail if the device's IP address changes.

Notes:
• Port Forwarding is not available in Access Point mode, as the Deco system does not function as a router in this mode.
• If you are using UPnP, be aware that some applications may dynamically request ports to be opened or closed, which can interfere with static port forwarding rules. If you suspect UPnP is causing issues, you may want to temporarily disable it and rely solely on manual port forwarding.
• For detailed configuration instructions, please refer to this FAQ: https://www.tp-link.com/support/faq/1797/

If the issue persists after confirming your port forwarding settings, consider rolling back the firmware (if possible) or contacting TP-Link support for further troubleshooting, as this may be a firmware-related bug.

Let me know if you need further assistance with these steps.