mikedb:
Where must the ''lock'' be changed?
It doesn't need to be changed. Just ignore that warning. It is the expected behavior and doesn't indicate any problem.
mikedb:
Where must the signature be changed?
You don't change the signature. You fix the problem that's causing the error.
Please do this:
- File > Preferences > Show verbose output during: > compilation (uncheck) > upload (check) > OK
- Tools > Burn Bootloader
- After the process fails you'll see a button on the right side of the orange bar "Copy error messages". Click that button.
- Paste the error messages in a reply here USING CODE TAGS (</> button on the toolbar).