Arduino won't upload

Hi!

Thanks for the help!

I tried your hint, but it seems there's some trouble with the chip itself...
Here is the error message I have when trying your command:

avrdude: initialization failed, rc=-1
avrdude: AVR device initialized and ready to accept instructions
avrdude: Device signature = 0x000000
avrdude: Yikes!  Invalid device signature.
avrdude: Expected signature for AT90USB82 is 1E 93 82
avrdude: NOTE: FLASH memory has been specified, an erase cycle will be performed
         To disable this feature, specify the -D option.

avrdude done.  Thank you.

Device signature = 0x000000 ? That doesn't seem right, right?
Should I try with -D ?