Ive installed xp on my acer travelmate 4100 laptop

hello!

-- who is your internet service provider
-- what is the operating system of your computer?
-- is this working fine before or is this a brand new router

you may try this and see if this help solve your problem

Step 1: Shutdown the computer.
Step 2: reset the router while power on then Unplug the router’s power cable.
Step 3: Unplug the Broadband modem’s power cable and wait for 30 seconds.
Step 4: Plug in the Broadband modem’s power cable and wait for its lights to appear stable.
Step 5: Plug in the router's power cable once the modem’s lights appear stable.
Step 6: Power on the computer on and configure the router settings
Step 7: test the Internet connection.