"failed to configure ethernet with dhcp"

I know that there are similar topics but i couldn’t find the solution in any of them

I use this sample sketch from arduino software, “Dhcp adress printer”

#include <SPI.h>
#include <Ethernet.h>

// Enter a MAC address for your controller below.
// Newer Ethernet shields have a MAC address printed on a sticker on the shield
byte mac[] = {  
  0x00, 0xAA, 0xBB, 0xCC, 0xDE, 0x02 };

// Initialize the Ethernet client library
// with the IP address and port of the server 
// that you want to connect to (port 80 is default for HTTP):
EthernetClient client;

void setup() {
 // Open serial communications and wait for port to open:
  Serial.begin(9600);
  // this check is only needed on the Leonardo:
   while (!Serial) {
    ; // wait for serial port to connect. Needed for Leonardo only
  }

  // start the Ethernet connection:
  if (Ethernet.begin(mac) == 0) {
    Serial.println("Failed to configure Ethernet using DHCP");
    // no point in carrying on, so do nothing forevermore:
    for(;;)
      ;
  }
  // print your local IP address:
  Serial.print("My IP address: ");
  for (byte thisByte = 0; thisByte < 4; thisByte++) {
    // print the value of each byte of the IP address:
    Serial.print(Ethernet.localIP()[thisByte], DEC);
    Serial.print("."); 
  }
  Serial.println();
}

void loop() {

}

every time i get this error “failed to configure ethernet with dhcp”, i tried to reset the arduino uno board and the ethernet shield, i have no sd card in the slot; my router it’s working fine and on the ethernet shield the leds are blinking so everything seems to work but i still get that error !

Please help, what should i do ? what can i try ? ideas ?

Moderator edit:
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tags added.