Hi. I have bought 2 of these but none have the MAC Address stick.How can I get it?Thanks

Don't know if you still care about this or not, but a new Ethernet library was released by someone who actually knows what he's doing.

https://www.pjrc.com/arduin...

No.
Your board arrived broken. Not functioning. Unable to post the IPaddress to the serial interface. I've wasted enough time, and pointless conversations with support that doesn't have enough consideration for their customers to believe they know what they're doing. Especially when the same code works on a competitors board.

I just threw your board out. You need a QA department in your manufacturing process.

Hi
The official library Ethernet.h manage W5100 chip, and Ethernet2.h manage W5500 chip, if you using this board, you don't need to use Ethernet 2 library, Ethernet.h is good for using.