after insert pen drive its not work. when I open it, it show a massage, " please insert a disk." but it show in my computer. it was a name but now it show Removable Disk. is it damage? the signal light not on.

My guess is that the drive is dead. Try using it in a computer with an operating system other than windows and see if it still doesn't work. If it works on another operating system, it could be your windows driver for the usb drive was corrupted and therefor it cant be read on your computer anymore.

i too facing the same problem in kingston's stick then i got it check from hardware lab..
and they said its dead......

regards.. :)