Troubleshooting Common Network Problems
Using Ping to Troubleshoot Network Problem
Sometimes if your network connection is down and you can use ping to troubleshoot network problem and then fix it. Ping is a program used to check whether a host is up and active in network. It’s pretty simple and usually used to troubleshoot network problem. Here is typical home network design, and the technique described applies to wireless network as well.
1) First thing you need to do is to make sure there is light on network card with cable connected. Sometimes network down is due to disconnected network cable or loose cable connection. If you notice no light on your network card after connecting with network cable, make sure the network cable is working and router that connected by this computer is up and active. If you see the light, then proceed to step 2.
2) Go to Start and click on Run.
3) Run window will appear. Type in cmd on Run window and click OK.
4) Key in ping 127.0.0.1 in Command Prompt window. This is network card loopback address. If you receive Reply from 127.0.0.1, it works. If you receive Request timed out, it means network card doesn’t work properly. Unplug and re-seat the network card, connect with network cable then ping loopback address again. If still fails, check the network card driver status in Windows 7, Vista or XP to troubleshoot network card and make sure the card works well. If still fails, most probably the network card cannot be used anymore. Try again by using other network cards. However if you just cannot install network card driver correctly on this computer but it works on other computer, then maybe there is problem on Microsoft Windows OS or its TCP/IP function.
5) Now you can proceed to ping your computer IP address. If you are not sure about computer IP, use ipconfig to find out. If you fail to ping this IP or no IP is configured on computer, check network configuration such as IP address (assigned manually or automatically?), subnet mask, gateway on network card to make sure it’s configured correctly.
6) If you able to ping loopback address and your computer IP, now you can proceed to ping router IP address. if you receive Request timed out, make sure router is up and configured properly with correct IP, subnet mask, DHCP and other network settings.
Note: Ensure that your DSL/Cable modem is configured in bridge mode (not routing mode), so that it can work well after connecting to router..
Note: Even if router is up and it’s configured properly, you need to check the computer is connected to correct and working router port too, sometimes it might be connected to faulty port or incorrect port (such as uplink port).
Note: If you have enabled firewall on router, make sure firewall is configured correctly without dropping legitimate network packets.
7)If you can ping the router IP, then you should be able to ping the other computers or notebook in your network
8) If you have successfully done above steps and all are working properly, but you still fail to connect to internet, then check your DSL, cable or wireless modem to make sure all cables are connected correctly. Reset your DSL, cable or wireless modem and try internet access after that. If your network is still down after that, contact your ISP for getting further helps to troubleshoot this network problem. This might due to some problems at your ISP side sometimes or the modem is broken.
Note: Sometimes you might find out your computer is connected to network, but just cannot browse Internet websites. So what to do next? Just use nslookup to try resolving the domain name, if there is problem then you can try to use the free DNS servers (184.108.40.206,
220.127.116.11) provided by OpenDNS.
Note: The other possibility, if suddenly you fail to access any webpage, maybe your computer is infected with adware, malware, worm or virus, so you should scan your computer by using antivirus or antispyware with latest signature.
Physical Network Connection Issue
Sometimes the wireless network connecting problem can be due to wrong network connection between the wireless router and DSL/Cable modem. You can take a look on this physical network setup below to ensure you have correct network setup.
Wireless Setup – Connecting Wireless Router
This is quick wireless setup. Before you configure the wireless router, you need to physical set it up first. Try to place the router in position that will best cover your wireless network. Usually the higher you place the antenna, the better the performance will be. Connect your cable/DSL modem to the WAN port of your wireless router by using straight Ethernet cable. Also you need to ensure that your cable/DSL modem is configured in bridge mode, so that it can work well after connecting to router. If you need more idea, here is an example of configuring DSL modem in bridge mode, feel free to take a look. After that, use another straight cable to connect router’s LAN port to your computer’s Ethernet port. Usually there are up to 4 or 5 LAN ports for you to connect to computers with network cable. The reason for connecting wireless router to your computer is to configure the router for the first time through web. You can remove the cable after router configuration.
After setting up the network, we need to decide what IP addresses need to be used for wireless router and computers. Click here for more explanation to do IP logical network setup and design. For the setup that I’m using, I use IP address 192.168.1.1-254, netmask 255.255.255.0.
Wireless Router Firmware Upgrade
If you have configured all the wireless settings correctly on wireless router, but still cannot connect to wireless network, then try to go to router manufacturer website to download latest router firmware and upgrade your router firmware. After that reconfigure the router and try to connect again. Sometimes the problem can be caused by the faulty router firmware. Also you can check on this wireless router configuration article to help you more.
DHCP Setting on Wireless Router
You must enable the DHCP setting on wireless router if you’ve configured the computer’s wireless adapter to obtain an IP address automatically. If not you will get the “failed to acquire an IP address” error when you try to connect to wireless network! Also don’t forget to configure big enough IP range on router’s DHCP setting, because the router won’t be able to assign IP to 6 computers if you only configured 5 IP space on router.
MAC Address Filtering Issue
Check whether you have enabled MAC address filtering on wireless router, if you have enabled it but your computer’s MAC address is not in allowed list, then of course you can’t connect to the network. If you did not enable it, then proceed to continue your reading.
Wireless Adapter Activation on Laptop
If you are using laptop with built-in wireless adapter, make sure you have activated the wireless adapter by turning on the wireless button, press Alt+F2 or other keys on the laptop. Read the laptop manual on how to activate the wireless adapter on laptop. As an example, usually I press Alt+F2 keys to activate wireless adapter on Dell Latitude laptop.
Wireless Adapter Driver Status and Configuration
Ensure you’ve installed the wireless adapter driver properly, if not it won’t work well. If possible, download the latest driver from manufacturer website and install it, this will fix the software bugs and hardware problems on existing adapter. The most important part is you need to configure the wireless adapter correctly, read these articles on how to configure wireless adapter in Windows 7, Vista and XP to see any incorrect configuration. If you think you have forgotten the wireless encryption key to join wireless network, try this WirelessKeyView to recover the wireless encryption key.
Wrong Configuration on DSL/Cable Modem
Ensure that your DSL/Cable modem is configured in bridge mode (not routing mode), so that it can work well after connecting to router. If you need more idea, here is an example of configuring DSL modem in bridge mode, you can have a look if you like. The other way to check is, if you need to use PPPoE dialer in Microsoft Windows in order to establish Internet connection with direct connection from computer to modem, then your modem is configured in bridge mode (correct mode).
Faulty Winsock or Registry in XP
Suddenly you just can’t connect to wireless network after some virus or malware cleaning, driver installation or software patching few days ago, then most probably it’s caused by faulty Winsock or registry in XP. How to tackle this problem? You can then try to use WinSockFix to solve it.
Note: The other possibility, if suddenly you fail to access any webpage but can connect to wireless network and Internet connection is up, then maybe your computer is infected with worm, virus, adware or malware, so you should scan your computer by using antivirus or antispyware with latest signature.
Using WinSockFix to Fix Windows XP Networking Problem
WinSockFix is also known as WinSock XP Fix! This is a popular program that usually used to fix Windows XP networking problem that caused by faulty WinSock or registry. If you encounter the following networking problems, and you have tried all other methods to resolve the problem but failed, then you can give this simple program a try.
– Internet or network problem after removing the adware, spyware, virus, worm, trojan horse, etc
– Loss network connection after installing/uninstalling adware, spyware, antispam, vpn, firewall or other networking programs
– No network connectivity due to registry errors
– Fail to renew the network adapter’s IP address or other DHCP errors
– Unable to access any webpage or can only access some webpages
– Pop-up error window with network related problem description
– Network connectivity issue with limited or no connections message (for wireless connection)
– System hang after installing the network adapter driver
– Very slow Internet connection after installing Windows XP SP2 or other programs
– DNS lookup problem
– Other networking problems
When you run the program, it will make changes on your registry in order to fix the winsock and network errors. The program can create a registry backup of your current registry settings, so it is quite safe to use.
1) Click here to download this WinSockFix if you want to try!
2) After downloading the program, you can just double click the program to run it. Advise you to click on ReG-Backup to backup the current registry first, after that click Fix to try solving your networking problem.
Note: When you backup the registry files, you can select the directory to save the registry backup.
3) Finally, you need to restart the computer, then test your network or Internet connection. Good luck!