Hi there! I understand that after the external network cable repair, the routers are not connecting to your internal network using the TP-Link Deco system. Let’s work through this step-by-step to get your network back up and running.

First, can you tell me:
1. Which Deco model you are using?
2. How is your network physically set up? (For example, modem > main Deco > satellite Deco units)
3. Are you trying to connect via Ethernet cable or Wi-Fi internally?
4. Did you notice any changes immediately after the cable repair, such as loss of internet on all devices or only some?

Meanwhile, here’s a general troubleshooting guide you can follow:

### Step 1: Check Physical Connections
- Make sure the repaired external network cable is properly connected to your modem and the main Deco unit’s WAN (Internet) port.
- Verify that the Ethernet cable from your main Deco to any internal network devices or satellite Deco units is firmly connected.

### Step 2: Power Cycle Devices
- Power off the modem, main Deco unit, and any satellite Deco units.
- Wait for about 1 minute.
- Turn on the modem first, wait until it’s fully online.
- Then power on your main Deco and satellite units.

### Step 3: Check Deco App Status
- Open the Deco app on your Windows device.
- Confirm the main Deco shows “Online” status.
- If the app shows no internet or “Disconnected” for your main Deco, try refreshing or restarting the app.

### Step 4: Verify Router Settings
- In the Deco app, under Internet settings, confirm the connection type matches your ISP’s requirements (DHCP, PPPoE, Static IP).
- If you use PPPoE, double-check your username and password.

### Step 5: Test Internal Network Connectivity
- Check if your internal devices can connect to each other via Wi-Fi or Ethernet.
- If internal devices are not communicating, the issue might be with how the Deco mesh system is handling LAN routing after the external cable repair.

If you have already done these steps, please let me know what you tried and the exact error messages or status you see. There are situations where losing the external internet connection can cause the Deco’s internal LAN ports to act unexpectedly, as sometimes the Deco gets “confused” on where the internet is coming from, affecting internal network access5.

I’m here to help you restore your network connection, so let me know the details and we will dig deeper into this! Are you satisfied with these initial steps so far?