Mega 2560 Upload Problems

I have been having trouble uploading sketches to my 2560 R2. I am using Windows XP. Sometimes everything works fine, and sometimes it will not work and times out with the message:

avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_getsync(): timeout communicating with programmer
avrdude: stk500v2_command(): failed miserably to execute command 0x11
avrdude: stk500v2_disable(): failed to leave programming mode

And then I try it again with no changes in between tries and it works fine. Needless to say this is a huge waste of time, although with patience I have always been able to get the sketches to upload eventually.
Anyone have a clue what's going on and how to fix it?
Thanks,
mike

HELPPP NEEDED HERE TOOOO

Do you guys have anything hooked up to the Mega's pins 0 & 1? Having anything hooked up to those pins may interfere with serial communication when programming.

no it's brand new i was testing it with the blink example :disappointed_relieved: never worked !!!

updated firmware to ATmega16U2 tried version 1.0, 0022 and 0023, nothing worked only Rx blinking with timeout errors just in the 0022 the led marked L blinked once when pressing the upload button

this is the upload on 0023 with shift :

Binary sketch size: 1588 bytes (of a 258048 byte maximum)
/Applications/Arduino.app/Contents/Resources/Java/hardware/tools/avr/bin/avrdude -C/Applications/Arduino.app/Contents/Resources/Java/hardware/tools/avr/etc/avrdude.conf -v -v -v -v -patmega2560 -cstk500v2 -P/dev/cu.usbmodemfa141 -b115200 -D -Uflash:w:/var/folders/tw/pvysvp5j30nfl10nlwfxkjn40000gn/T/build3435776181375428451.tmp/Blink.cpp.hex:i

avrdude: Version 5.4-arduino, compiled on Oct 9 2007 at 11:20:31
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/

System wide configuration file is "/Applications/Arduino.app/Contents/Resources/Java/hardware/tools/avr/etc/avrdude.conf"
User configuration file is "/Users/ahmadzein/.avrduderc"
User configuration file does not exist or is not a regular file, skipping

Using Port : /dev/cu.usbmodemfa141
Using Programmer : stk500v2
Overriding Baud Rate : 115200
avrdude: Send: . [1b] . [01] . [00] . [01] . [0e] . [01] . [14]
avrdude: ser_recv(): programmer is not responding
avrdude: stk500_2_ReceiveMessage(): timeout
avrdude: Send: . [1b] . [01] . [00] . [01] . [0e] . [01] . [14]
avrdude: ser_recv(): programmer is not responding
avrdude: stk500_2_ReceiveMessage(): timeout
avrdude: Send: . [1b] . [01] . [00] . [01] . [0e] . [01] . [14]
avrdude: ser_recv(): programmer is not responding
avrdude: stk500_2_ReceiveMessage(): timeout
avrdude: Send: . [1b] . [01] . [00] . [01] . [0e] . [01] . [14]

any idea !?!?! pleaseee helppp

everyone. I have had the same problem with my board! I am able to make it work by first connecting through realterm. If I do that first... then program using the gui like normal it works? Why, I don't know...

Guys. I used the avrdude.exe and avrdude.conf file from 022 and it worked fine for me. There seems to be a bug in avrdude 5.11 that is causing some of these issues. But if 022 didn't work, then maybe you have worse problems?

Use "wiring" instead of "stk500v2" : work's fine on Mega2560 R3 8)

Hi,
Sorry about the delay in replying. There is nothing hooked up to any pins. I am only running sketches on the 2560 and watching the serial output to see how it functions. How can I use "wiring" to upload instead of avrdude?

Be sure your code hasn't any string with "!!!" inside

This is not a joke:
http://code.google.com/p/arduino/issues/detail?id=797