Down Speed & WiFi Not Working: Complete Troubleshooting Guide for Slow Internet, No Connection & Can't Connect to Network

Understanding Slow Download Speed and WiFi Connection Failures

When your download speed is far below what you pay for, or your device shows 'connected but no internet,' the problem almost always falls into one of three layers: your device, your home network hardware, or your ISP. The key to fast resolution is isolating which layer is failing before you start changing settings.

Step 1: Determine the Scope of the Problem

Before touching any settings, answer these questions:

1. Is it one device or all devices? If only your laptop is slow but your phone is fast, the problem is device-specific. If everything is slow, the issue is the router, modem, or ISP.
2. Is it WiFi-specific or also on Ethernet? Plug directly into your router or modem with an Ethernet cable and run a speed test at fast.com or speedtest.net. If wired speed is normal but WiFi is slow, your router's wireless radio, placement, or interference is the culprit.
3. Is the speed slow all day or only at night? Slowdowns between 7–11 PM strongly indicate ISP network congestion or throttling.
4. Check your ISP's status page — Cox, CenturyLink, Frontier, Google Fiber, Optimum, Breezeline, and T-Mobile Home Internet all maintain real-time outage dashboards.

Step 2: Power-Cycle Your Network Hardware (Correct Order)

This resolves the majority of 'connected but no internet,' slow speed, and 'can't connect to this network' issues by clearing stale DHCP leases and resetting the modem's link to your ISP.

1. Unplug your modem from power (and coaxial/phone line if applicable). Wait 60 seconds — not 10.
2. Unplug your router from power. Wait 30 seconds.
3. Plug the modem back in and wait until its online/internet indicator light is solid (usually 1–2 minutes).
4. Plug the router back in and wait another 60 seconds before testing.
5. Reconnect your device and run a speed test.

Step 3: Diagnose on Windows (CMD Commands)

Open Command Prompt as Administrator and run the following sequence:

ipconfig /release
ipconfig /flushdns
ipconfig /renew
netsh winsock reset
netsh int ip reset

After these commands, restart your PC. This fixes most cases of:

• 'Unidentified network' on Ethernet
• IPv4 connectivity: No network access
• IPv6 connectivity: No network access
• Connected to WiFi but no internet access

Step 4: Fix 'Can't Connect to This Network' on Windows 10/11

This specific error usually means Windows has a corrupted or mismatched network profile saved for that WiFi network.

1. Go to Settings → Network & Internet → WiFi → Manage Known Networks.
2. Find the problematic network and click Forget.
3. Reconnect by searching for the network and entering the password fresh.
4. If the error persists, open Device Manager, expand Network Adapters, right-click your WiFi adapter, and select Uninstall device (check 'Delete driver software'). Restart Windows — it will reinstall the driver automatically.
5. For Intel WiFi adapters (AC 9560, AX200, AX201, AX210): download the latest driver directly from Intel's Driver & Support Assistant.

Step 5: Fix Slow Download Speed on a Specific Device

On Windows:

• Open Device Manager → Network Adapters → right-click WiFi adapter → Properties → Advanced tab.
• Set Roaming Aggressiveness to Lowest, Preferred Band to 5 GHz, and disable Power Saving Mode.
• Change DNS: Go to Network Settings → Change adapter options → right-click adapter → Properties → IPv4 → Use the following DNS: Primary 8.8.8.8, Secondary 1.1.1.1.

On Mac:

• Apple Menu → System Settings → Network → WiFi → Details → DNS tab → add 8.8.8.8 and 1.1.1.1.
• Run in Terminal: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder

On Android/iPhone:

• Forget the WiFi network and reconnect.
• Toggle Airplane Mode on for 15 seconds, then off.
• For Android: Settings → Network → WiFi → Long-press network → Modify → Advanced → IP Settings: change to Static, set DNS 1 to 8.8.8.8.

Step 6: Fix 2.4 GHz Not Working / 5 GHz Not Showing Up

Dual-band issues (where one band works but the other does not) are common on ASUS AiMesh, Nighthawk, TP-Link Deco, and Google Nest systems.

• Log into your router admin page (typically 192.168.1.1 or 192.168.0.1).
• Ensure both 2.4 GHz and 5 GHz radios are enabled separately.
• Check that the SSID names are distinct if band-steering is disabled.
• Update router firmware via the admin panel — outdated firmware is the #1 cause of band failures.
• For Nighthawk routers: navigate to routerlogin.net → Advanced → Wireless Settings and verify both bands show 'Up.'

Step 7: Slow Upload Speed Fix

Slow upload speed (while download is normal) is often caused by:

• QoS (Quality of Service) misconfiguration in the router — log in and disable or reconfigure QoS.
• Upload throttling by ISP — especially for Cox, Mediacom, and cable-based ISPs. Run an upload test at speedtest.net using a VPN; if upload improves, contact your ISP.
• Half-duplex Ethernet — check that your Ethernet adapter is set to Auto-Negotiation in Device Manager → adapter properties.
• Wireless interference — switch your router's 2.4 GHz channel to 1, 6, or 11 to reduce overlap with neighbors.

Step 8: Router-Specific Troubleshooting

Cox Panoramic WiFi / Cox Router:

• If blinking orange: the modem is trying to connect to Cox's network. Check cox.com/myaccount for outages.
• Log in at 192.168.0.1 with admin credentials on the label.

Netgear Nighthawk (routerlogin.net not working):

• Try 192.168.1.1 directly. Clear browser cache or try incognito mode.
• Factory reset by holding the reset button for 10 seconds.

CenturyLink / Quantum Fiber:

• Log in at 192.168.0.1. If 'Can't connect to this network' appears, check the PPPoE username/password under Internet Settings.

Frontier Router:

• To restart: hold the reset button for 5–7 seconds (not full factory reset). Check frontier.com/local/service-outages.

Google Fiber slow speeds:

• Check the Google Fiber app for node status. Reboot the Network Box via the app. If all nodes show green but speeds are low, contact Google Fiber support — backend congestion is common.

Step 9: LG TV / Smart TV WiFi Not Working

LG TV 'WiFi is turned off' is one of the most searched TV connectivity issues. Follow this sequence:

1. Go to Settings → All Settings → Network → WiFi Connection and toggle WiFi on.
2. If WiFi option is greyed out or says 'turned off': perform a soft reset — hold the power button on the TV (not remote) for 10 seconds.
3. Go to Settings → General → Reset to Initial Settings only as a last resort.
4. If the TV finds networks but can't connect: delete the network profile, re-enter the password, and set DNS manually to 8.8.8.8.

Step 10: When to Call Your ISP

Call or chat with your ISP if:

• Wired speed test (direct modem connection) shows speeds significantly below your plan.
• Multiple devices across your home are slow or disconnected simultaneously.
• The issue started after a weather event, construction nearby, or a billing change.
• You've power-cycled everything and the modem's upstream/downstream channels are still off in the admin page (192.168.100.1 for most cable modems).
• For Cox: call 1-800-234-3993 or use the Cox app. For CenturyLink: 1-800-244-1111. For Frontier: 1-800-921-8101.