do not worry about it..
if you are still online with the desktop..
Step 1:
Open a web browser such as Internet Explorer.
Step 2:
Go to the Address bar and enter your router’s IP Address ("192.168.1.1" is the default IP of most Linksys routers) then press [Enter].
If should ask for a user name and a passwd.. if it is not ..try with 192.168.2.1 or 192.168.5.1 if still not..
then for a dsl connection you might have changed the ip address of your router..
To check ipaddress
click start then run and in run type cmd and click ok..
you would be in a black dos prompt..
type ipconfig and press ok.. you would find the ipaddress
Step 3:
Open a web browser such as Internet Explorer.
Step 4:
Go to the Address bar and enter your router’s IP Address
then press [Enter].
Step 5:
When the router’s web-based setup page appears, click the Wireless tab.
Step 6:
Look for Wireless Network Name (SSID) and if it’s still set to ‘linksys’ change it to something unique then click Save Settings. or else if the name is changed leave it..
ans below the wireless tab select the Wireless Security sub tab.in the blue bar. check for the defalt transmit key and key 1 if its already setup, then make a note of the key and go to Step 12 if not setb up wireless security first
Step 7:
Select any number under the Default Transmit Key to determine which key you’ll be using. In this example, we selected number 1.
Step 8:
Select 128 bits under WEP Encryption.
Step 9:
Type a wireless network password of your choice such as “MySecretKey”, then click Generate.
NOTE: You should come up with a password that is unique for your network and is a combination of numbers and letters up to 26 characters.
Step 10:
The result will be a string of random characters. Copy the resulting string since this will be the key to your wireless network.
NOTE: Do not give this key to anyone. This will be your wireless network’s key.
Step 11:
Click

.
Step 12:
now go to your latop. right click wireless network connectios icons and click view wireless network.. (if it is xp os)
you would fine the name of the n/w try connecting to it, it would ask for the n/w key enter the 26 digit key which you have setup and click connect, you would go online with your laptop..