Network Issues – Troubleshooting Guide

Welcome to the comprehensive guide for diagnosing and resolving common network problems. Use the sections below to quickly find solutions or explore step‑by‑step procedures.

Common Connectivity Problems+

• No internet access
• Intermittent drops
• Slow bandwidth
• DNS resolution failures
• VPN connectivity issues

Diagnostic Tools+

• ping – test reachability
• tracert / traceroute – route tracing
• nslookup / dig – DNS checks
• netstat – view connections
• Wireshark – packet capture

Step‑by‑Step Guides+

Reset Network Adapter
Flush DNS Cache
Check Firewall Settings
Reboot Router/Modem

FAQ+

Q: Why does my Wi‑Fi keep disconnecting?
A: Interference, outdated drivers, or router channel congestion are typical causes.

Q: How can I test if the issue is local?
A: Connect a device directly via Ethernet; if it works, the problem is likely wireless.

Reset Network Adapter

Open Settings > Network & Internet.
Click Change adapter options.
Right‑click the affected adapter and select Disable.
Wait 10 seconds, then Enable the adapter.
Confirm connectivity with ping 8.8.8.8.

Flush DNS Cache

Windows:  ipconfig /flushdns

macOS:    sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder

Linux:    sudo systemd-resolve --flush-caches

Check Firewall Settings

Ensure that your firewall isn’t blocking essential ports (e.g., 80, 443, 53). Use the built‑in firewall logs or your security suite to verify.

Reboot Router/Modem

Power off the router and modem.
Wait 30 seconds.
Power them back on – wait for all lights to stabilize.
Retest connectivity.