I am using a wirless router and sharing the internet connection between the desktop and laptop, how to set up the secure network on the wireless router to prevent the unauthorized user to logon to my wireless network to shared the internet connection... pls help.

Okay, you are going to have to give more information. All routers are set up differently. Enabling WEP Encryption is simple but it depends on the brand of router you are using. The easiest solution and most quick is simply to call the router manufacturer for free support. They will walk you right through it.

I agree that WEP is the best way to accomplish this, and is sometimes complex.

But there are other effective option. Using a MAC filter is sometimes much easier (not as good, but good enough in most home LANs).

When you get into your router configuration, you can go to the "wireless security" section, and there is usually a sub-menu that says "MAC filter".

You can click the "clients" tab and get a list of computers in your network.

Match the MAC address up that belongs to your computer by going to:
:: Start - RUN, then type "cmd" press "OK", now you are at the DOS screen. Type "ipconfig /all" The last thing listed will be the "physical address"
Get the "physical address" for the "wireless connection" (that will be listed above and you may have more than one adapter, so look carefully).

Write that address down, and match it up in your router configuration where we left off.

Let your router allow that address access or "permit".

It all depends on the equipment.

If your router has a "help file" in the configuration section. You can easily learn how WEP works.

To get to the router configuration, connect your PC with a Ethernet cable to the router. Type in the gateway address (this can also be found by going to IPCONFIG /ALL), or look in the instruction manual. Usually it is something like: 192.168.1.1 or some variation of that address.

Once you get to the correct configuration page in your router web interface, be sure to do at least ALL of the following:

1) Turn on encryption. WEP is okay but certainly not breakable. Use something stronger if it is supported. Set a passphrase.
2) Disable SSID broadcast.
3) Change the default SSID name
4) Turn on the MAC address filter, as described above.