I have already tried below suggestion which i found from forums.
1 dump the arduino-usbserial-atmega16u2-Mega256-Rev3.hex for atmega16u2
2 dump the stk500boot_v2_mega256.hex for atmega2560
3 Tried to check the com port.(already port selected in devicemanager and com port are same in arduino IDE and device manager,Device manager is showing the Atmega2560 board.
4 Tried the Reset solution.
5 While dumping my Rx Led is also glowing .
I have already worked for 2 week for diffrent suggestion but till now was not able a single programme
in it.so anybody has solved this issue please suggest something.
You say you "dump" the firmware. That is probably not the right word - "dumping" the firmware would mean copying it from the microcontroller to a file, which doesn't make sense in context. What did you do, and how? Was it successful?
I have loaded the hex file through atmel ISP programmer through atmel stdio 6.2 in atmega2560 and atmega16u2 and it was successful also without any error.
I tried to check even by erasing the code from the atmega2560 to check the L led response it was staying "ON" continuosly but not blinking on reset .
Then again i loaded Hex file "stk500boot_v2_mega256.hex for atmega2560" throgh atmel isp programmer and again it started blinking but still when i load a simple blink program through arduino via USB cable it is showing me the same error.
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_getsync(): timeout communicating with programmer
If you want to be successful with programming and getting effective advice from your questions you need to get into the habit of being precise. It may just be a missing letter here and there and likely we still understand what you mean in this case but the compiler surely won't. Everyone makes a typo from time to time but it's best to be as precise as possible in technical matters. Taking a minute to proofread and correct your posts may save us some time and make it more likely that your problem is solved more quickly. I realize that many forum users don't speak English as their first language and you all certainly are more fluent in English than I am in your language but these sorts of typos are not language dependent.