Overview

Internet connection issues have many causes. This guide walks through systematic troubleshooting from simple checks to advanced fixes, resolving most home connectivity problems.

Step 1: Basic Checks and Quick Fixes

1

Check Multiple Devices

Try internet on phone, laptop, tablet
If only one device affected: problem is device-specific
If all devices affected: problem is router or ISP
Test both Wi-Fi and wired connections

2

Check Router and Modem Lights

Normal modem lights:

Power: Solid green/white
Internet/Online: Solid green/white (connected)
Flashing: Modem trying to connect
Red/amber: Connection problem

Router lights:

Power: Solid
Internet/WAN: Solid (has connection from modem)
Wi-Fi: Solid or flashing (active)

3

Verify Physical Connections

Check all cables firmly connected
Ethernet cable from wall to modem (Internet/WAN port)
Ethernet cable from modem to router WAN/Internet port
Power cables plugged in securely
Look for damaged cables (kinks, cuts, chewed by pets)
Unplug and replug all connections

4

Check for Service Outages

Use mobile data to check ISP's status page
Check Downdetector.com for reported outages
Call ISP support number (have account number ready)
Ask neighbours if their internet working
If widespread outage, wait for ISP to restore service

5

Toggle Airplane Mode (Mobile Devices)

On phone or tablet, enable Airplane mode
Wait 10 seconds
Disable Airplane mode
Device reconnects to Wi-Fi
Often fixes temporary connection glitches

Step 2: Reset Modem and Router

1

Power Cycle Modem and Router (Correct Order)

Unplug power cable from modem
Unplug power cable from router
Wait 30 seconds (clears memory)
Plug modem back in first
Wait until all lights stable (2-3 minutes)
Then plug router back in
Wait for router lights to stabilise
Test internet connection

Why This Works:

Power cycling clears temporary errors, renews IP addresses, and re-establishes connection between devices. Fixes 80% of connection issues.

2

Factory Reset Router (Last Resort)

Only if power cycling doesn't work
Find reset button (usually recessed hole on back)
Press and hold with paperclip for 10-30 seconds
Router lights flash and restart
Router resets to factory defaults
You'll need to reconfigure Wi-Fi name and password

Warning:

Factory reset erases all settings including Wi-Fi name, password, and custom configurations. Only use as last resort.

3

Test with Direct Modem Connection

Disconnect router from modem
Connect computer directly to modem with Ethernet cable
Power cycle modem
Test internet on computer
If works: router is faulty
If doesn't work: modem or ISP issue

Step 3: Windows Network Troubleshooting

1

Run Windows Network Troubleshooter

Settings → Network & Internet → Status
Click "Network troubleshooter"
Follow on-screen instructions
Windows detects and fixes common issues automatically
May reset network adapter or renew IP

2

Flush DNS Cache

Search for "Command Prompt" or "cmd"
Right-click → Run as administrator
Type: ipconfig /flushdns
Press Enter
Message: "Successfully flushed the DNS Resolver Cache"
Clears corrupted DNS entries

3

Reset Network Stack

Command Prompt (Administrator)
Type these commands one by one, pressing Enter after each:
netsh winsock reset
netsh int ip reset
ipconfig /release
ipconfig /renew
Restart computer

4

Update or Reinstall Network Adapter Driver

Device Manager → Network adapters
Right-click Wi-Fi or Ethernet adapter
Select "Update driver"
Choose "Search automatically for drivers"
If no update: Right-click → Uninstall device
Restart computer (Windows reinstalls driver automatically)

5

Disable and Re-enable Network Adapter

Settings → Network & Internet
Change adapter options
Right-click network adapter → Disable
Wait 10 seconds
Right-click → Enable
Wait for connection to re-establish

Step 4: Advanced Troubleshooting

1

Change DNS Servers

Settings → Network & Internet → Change adapter options
Right-click adapter → Properties
Select "Internet Protocol Version 4 (TCP/IPv4)"
Click Properties
Select "Use the following DNS server addresses"
Preferred DNS: 8.8.8.8 (Google)
Alternate DNS: 8.8.4.4
Or use Cloudflare: 1.1.1.1 and 1.0.0.1
Click OK and test connection

2

Check IP Address Assignment

Command Prompt: ipconfig
Look for IPv4 Address under your adapter
Should start with 192.168.x.x or 10.x.x.x
If shows 169.254.x.x: DHCP failed
Run: ipconfig /release then ipconfig /renew
If still 169 address, router DHCP may be disabled

3

Disable VPN or Proxy

VPN software can block connections if misconfigured
Disable VPN temporarily and test
Settings → Network & Internet → Proxy
Ensure "Automatically detect settings" is ON
Ensure "Use a proxy server" is OFF

4

Check Firewall and Antivirus

Temporarily disable antivirus and test
If internet works: antivirus blocking connection
Add exception or reinstall antivirus
Windows Defender Firewall rarely causes issues
Third-party firewalls sometimes block legitimate traffic

5

Test Different Wi-Fi Band

If dual-band router, try both 2.4GHz and 5GHz
2.4GHz: Better range, more interference
5GHz: Shorter range, less interference
Disconnect from current network
Connect to other band and test

6

Contact ISP Support

Call ISP if:

Modem lights show connection problem
Direct modem connection doesn't work
All troubleshooting steps failed
Frequent disconnections persist

Have ready:

Account number
Description of problem
Modem light status
Steps already tried
ISP may schedule technician visit or replace equipment

7

Consider Hardware Replacement

Router older than 5 years may be failing
Frequent disconnections despite troubleshooting
Slow speeds not matching ISP plan
Modern routers support newer Wi-Fi standards
Cost: £50-£200 depending on features