I am new to arduino, I have an Arduino Uno and an Ethernet shield w5100.
I am trying an example sketche on the Ethernet library from this link.
Ethernet Tutorial from Arduino website
I used the DhcpAddressPrinter example sketch. but it returns Failed to configure Ethernet using DHCP on the serial monitor.
The Arduino is connected to the router with DHCP enable. My laptop is connected to the same router and was able to acquire IP with no problems.
Have you seen this thread: https://forum.arduino.cc/index.php?topic=351477.15
unfortunately it requires use of a soldering iron....
I have confirmed myself: a cheap 'no-name' board I had exhibited the same problem you describe above. I bought one from "JayCar" (in Australia) and the same program rang perfectly.
The resistor on the cheap "no-name" board was the wrong value. Although the cheap and JayCar board looked almost identical, the resistor soldered on the JarCar board was a different resistance to the resistor soldered on the cheap board.
This causes the cheap board to not work reliably.
