Upload Timeout Error on Mega 2560 - Not Sure What Changed

Guys!

It's been 5 years and this problem is still actual.
I'm zero in programming, so I use maxuino to do my projects!
Was just trying to upload the standard firmata on my arduino atmega 2560.
The usual mistake:
avrdude: stk500v2_ReceiveMessage(): timeout
keeps coming out.

I read the whole thread and tried to do anything I had a decent understanding about: like installing different firmware (0023 ecc).

But the mistake stays.

I see here really experienced people.
Is there anybody, that could help me on this one?

Thank you a lot!!

Alexander