I've been using arduino-0009 without any problem. Today i've installed 0011 and problems have come.
I can't burn any sketch, i get this error always:
Binary sketch size: 3184 bytes (of a 14336 byte maximum)
avrdude: Yikes! Invalid device signature.
Double check connections and try again, or use -F to override
this check.
The same sketch can be burn with 0009 version.
Help please!
Are you sure you have chosen the right board in the tools -> microcontroller menu? I don't think each version of the IDE remembers your settings from previous versions