beginner question - useing the ethernet

Hello ,
I’m using the sparkfun Pro Ethrnet
and I want to give (for start) an IP to the card and to see I can reach him by ping

this is my code (very simple)
#include <Ethernet.h>

byte mac = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
byte ip = {10,0,0,155};

void setup(){
Ethernet.begin(mac , ip);
}

and I get an error message

libraries\ethernet\dhcp.cpp:4;
libraries\ethernet\utility/w5100.h:14:17:error:SPI.h:No such file or directory

why is it?
I have this file on the computer in the directory that are mention.

please help - Thank you!

You must include the SPI.h header.

#include <SPI.h>
#include <Ethernet.h>
// rest of your code

O.k Thank you !