Upload a hex file trouble

hi all,

i made a mistake and upload the grbl hex file with xloader, ? am using the adafruit motorshield to make a desktop cnc (also ? couldnt manage to work the cnc) now ? am tring to upload a led blink code with aruino software but it doesnt work what should i do how can ? fix the problem or where can ? find the uno rev3 hex file?

Once you upload a program through the ICSP header you have to re-load the bootloader. If you are going to be doing that much you should invest a few dollars in an ICSP Programmer like a USBasp. You might also want to get a 10-pin to 6-pin adapter since the USBasp usually comes with a 10-pin cable and the Arduino has a 6-pin header.