Better error message for "avrdude: stk500_getsync(): not in sync" [imported]

This is [Issue 868](http://code.google.com/p/arduino/issues/detail?id=868) moved from a Google Code project.
Added by 2012-03-29T13:10:59.000Z by [tom.i...@gmail.com](http://code.google.com/u/102867599453860860098/).
Please review that bug for more context and additional comments, but update this bug.

Original labels: Type-Defect, Priority-High
### Original description

We need a more informative error message for:

avrdude: stk500_getsync(): not in sync: resp=0x30

I get at least one request a week for what this means, from beginners. It's usually one of several things, but basically the fact that the Arduino isn't responding. We need a better error message for it.

**What steps will reproduce the problem?**
1. Not connecting the Arduino
2. Or a short circuit on the board
3. Or a damaged bootloader
4. Or many other things

What is the expected output?

"Your Arduino isn't responding. Check to see if it's connected, or if there is a short circuit on the board."

What do you see instead?

A line of terse, unfriendly programmer-speak:
avrdude: stk500_getsync(): not in sync: resp=0x30

Start by reviewing the linked original Issue 868 and locating where the shown avrdude output is surfaced; the payload names no repository file or test. Done means replacing the terse message with an informative warning that covers the Arduino connection, short-circuit, and related failure cases.

Written by the indexing model from the issue text.