Arduino mega 13 LED always on

I have a sainsamart arduino mega2560. I used it for a couple of days but now it is not working. The onboard LED(13) is always on. Even if I press the reset button, nothing happens.
When uploading a code the following error comes. And the 13 LED remains on. I am a complete noob in arduino so please help.

Arduino: 1.6.6 (Windows 8.1), Board: "Arduino/Genuino Mega or Mega 2560, ATmega2560 (Mega 2560)"

Sketch uses 1,518 bytes (0%) of program storage space. Maximum is 253,952 bytes.
Global variables use 9 bytes (0%) of dynamic memory, leaving 8,183 bytes for local variables. Maximum is 8,192 bytes.
avrdude: ser_open(): can't open device "\\.\COM11": Access is denied.


avrdude: ser_drain(): read error: The handle is invalid.


Problem uploading to board.  See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.

  This report would have more information with
  "Show verbose output during compilation"
  enabled in File > Preferences.

What happens when you load an empty sketch?

Setup ()
Loop()

Weedpharma

I got the same error…

Just noticed

“avrdude: ser_open(): can’t open device “\.\COM11”: Access is denied.”

Go into “Tools” and “Serial Port” and select the port that the Arduino is attached to.

Weedpharma

You may want to try another usb cable or usb port

Sketch uses 1,518 bytes (0%) of program storage space. Maximum is 253,952 bytes.
Global variables use 9 bytes (0%) of dynamic memory, leaving 8,183 bytes for local variables. Maximum is 8,192 bytes.
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_getsync(): timeout communicating with programmer

that error comes sometimes.
I have selected the correct port,board and tried with other usb cables. :frowning: