my arduino is not readable on the Pc after burning avr program on its atmega

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1

after i burned avr program on the atmega of my leonardo the led is always light and not readable on the devices manager but i still can read the signature of the atmega and program it what i can do to reuse the arduino as arduino ?

2

I think you need to re-install the bootloader. Perhaps this will help:
http://forums.adafruit.com/viewtopic.php?f=19&t=23070