Before I got my laptop, I only used my desktop to go online. When my laptop arrived, I unplugged the internet cable connecting modem to my computer and connected a new one to my laptop. When I want to use my desktop to go online, I just switch the internet cables. After a week of doing that though, my laptop suddenly shows that I have three broadband connections (all connects using the same password), and my desktop couldn't connect anymore. My desktop could always connect before, so I assume I clicked the wrong things on my laptop that caused this connection problem. My desktp is windows XP while my laptop is Windows 7Yuwei Lu

I don't think that the issue is with Desktop or Latptop but your insternet connection.Please contact your ISP and they would help you with. There are a certain ISP that uses MAC address for authentication , there could be a possbility that a MAC address is registered there and so the other computer is not able to connect. Once you have your ISP issue resolved , get a ROUTER , with the help of that both laptop and desktop can go online without changing the cabe.