hey guyz i just installed a new sony dvd-writer on my machine and everything was fine until suddenly i got a BSOD and there was some error regarding usb configuration and it stated that "a recent hardware or software change might have caused it or something". i ignored it and things were still smooth but i now i am having a weird problem.... my usb devices dont get detected when i plug them into any usb port ... for example my usb thumb drive does not get detected when i plug it in .. but if i restart the system then it works fine. this occurs randomly and without any errors/warning. what is the problem ? and ya my system stops responding especially the device manager and xp does not shut down also... just gets stuck at the shutting down screen. plz help. thanx.