Help troubleshooting

Just this afternoon while I was busy surfing... my internet stopped working.I hve Winxp and Airtel 220BX modem on LAN.I disabled my firewal... checked for suspicious services.... checked enteries in the HOSTS file... but nuthin seems to work.I uninstalled my NIC... disabled my connection... which is currently through DHCP.Still no luck..! 🙁Although in the afternoon... net was not workin in Linux... but rite now it is. So there is no problem in the connectivity... but sum problem in Windows I think??Any guesses??!!