TroubleShooting is a Complex Process. That Requires Skill and a Little Logic.

If you are able to Differentiate the Software and Hardware Problems first...

...then you can do troubleshooting much easier.

It is often recommended to start the troubleshooting process with hardware problem on your network.

The reason is simple. You may experience this problem after the installation of any new software.

You can start the process of troubleshooting by checking the IP address of the network first.

Sometimes the IP address may be the address of the router too and so it is advisable to see the instructions before checking.

In order to check the IP address of the network, it is wise to use Control Panel or Network connections. However, it is far better to diagnose any of the issues in the network by executing command line utilities.

You can open the DOS window by clicking Start\run

and by typing “cmd” in the dialog box.

Next, type “ipconfig” to display the IP address.

If you have three or more computers connected to a hub and uses internet connection sharing, then it forms a network. While checking IP address,

you need to take effort to check the IP address for the second and third computer on the network.

You can check the address sequentially and then check it again in the reverse order.

This helps you to segregate the problem in any of the other computers.

It is also essential to check the lights on the Network adapter...

...on all the computers. When you do the checking, the lights should be blinking and green.

It is equally important to check the hub to which all the three computers are attached, also blinking. 

If any of the lights do not light, or flicker continuously, then the problem may be in the cable that is attached to the port. There may be a chance that the cable or connector is loose.

Sometimes, the cable or connector may get bent because of physical stress.

This may also lead to malfunctioning of the unit. Any such fault may cause the whole cable to function improperly.

If you have wireless network, then check...

...the adapter and router.

This can help you isolate the problem easily...

There is yet another form to troubleshoot the home network,

I asume you can get to the command prompt (cmd) Start/All Programs/Accessories - command prompt

You can use “tracert” command instead of using ping method. It is advisable to execute “tracert” within DOS windows.

Ping your computer from the command prompt: ping 127.0.0.1
It should look like this

Tip: Sometimes files get messed up, so make sure your in the system32 directory, but first try it from the command prompt that opens. You might not have to change anything.

C:\WINDOWS\system32>ping 127.0.0.1

Pinging 127.0.0.1 with 32 bytes of data:

Reply from 127.0.0.1: bytes=32 time<1ms TTL=128
Reply from 127.0.0.1: bytes=32 time<1ms TTL=128
Reply from 127.0.0.1: bytes=32 time<1ms TTL=128
Reply from 127.0.0.1: bytes=32 time<1ms TTL=128

    Ping statistics for 127.0.0.1:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
    Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms

This is good your (NIC) network card is working, fine. Now can you reach your router? , maybe another computer on your wireless/cabled network.

PIng your router, this your default Gateway and DHCP server. which resides at 192.168.1.1 (linksys)
Always check the manual, first. Some routers will be different

C:\WINDOWS\system32>ping 192.168.1.1

Pinging 192.168.1.1 with 32 bytes of data:

Reply from 192.168.1.1: bytes=32 time=134ms TTL=64
Reply from 192.168.1.1: bytes=32 time=1ms TTL=64
Reply from 192.168.1.1: bytes=32 time=1ms TTL=64
Reply from 192.168.1.1: bytes=32 time=1ms TTL=64

Ping statistics for 192.168.1.1:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% lo
Approximate round trip times in milli-seconds:
    Minimum = 1ms, Maximum = 134ms, Average = 34ms

Folks, I'm working on more TroubleShooting tips for this page for stay tuned