Start ---> All Programs ---> Accesseries ----> Right Click on Command Prompt, and select Run as Admin. Now the commands in order:
You should see a default gateway v4 listed. It will either start with 192 or 10. If you see this, go to #2. If you see no gateway, but either a 0.0.0.0 or a 169.254.X.X IPv4 Address, go to #3
2) ping abc.com
If you get replies, your system is connected. If you get timeouts or "cannot find host", then it's either a virus or something blocking your connection. It's not the modem or router since the laptop connects.
3) netsh i i r r
netsh winsock reset catalot
Run them both together, then reboot after the Winsock is reset. This resets the TCP/IP information. Once reboot, check ipconfig.
4) If you still got a 169.254 or 0.0.0.0 IP address, try removing the wifi network and reconnect it. If you still can't connect, it's a bad wifi card at that point.