program upload error when ethernet shield plugged

sorry if i post in wrong category. i just bought an ethernet shield, when i plugged the shield to arduino, the program cannot be uploaded.
if i remove the shield i can upload the program and it can run, but after the shield plugged again the program doesnt run.
Arduino IDE displays

avrdude: Recv: 
avrdude: stk500v2_ReceiveMessage(): timeout
avrdude: stk500v2_getsync(): timeout communicating with programmer

the ethernet shield labelled HanRun HR911105A 16/02

Please post the code that you are using, and give us a link to the shield.

i use example from arduino IDE

void setup() {
  // initialize digital pin 13 as an output.
  pinMode(7, OUTPUT);
}

// the loop function runs over and over again forever
void loop() {
  digitalWrite(7, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(1000);              // wait for a second
  digitalWrite(7, LOW);    // turn the LED off by making the voltage LOW
  delay(1000);              // wait for a second
}

i think its similiar with this