Intex IT 350WC is not detected

Hello,
i have been using this INtex IT-350WC webcam since about 8 months ago..it was always connected to my front usb port and it was working fine.. but suddenly i found that my usb port where i had intalled it and which was working fine is no more detected. i reinstalled it and installed it in new port but no use.. when i installed it in new port it was detected but after i restarted my computer it was not detected... most surprisingly it was detected in dell laptop but when i tried it in desktop it is not detected... plzz plzzz help me out.....