error code TKD2

Arduino: 1.6.8 (Windows 10), Board: "Arduino/Genuino Uno"

C:\Program Files (x86)\Arduino\libraries\RobotIRremote\src\IRremoteTools.cpp:5:16: error: 'TKD2' was not declared in this scope

int RECV_PIN = TKD2; // the pin the IR receiver is connected to

^

exit status 1
Error compiling for board Arduino/Genuino Uno.

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

This is the code im using
#include <IRremote.h>

int RECV_PIN = 11;

IRrecv irrecv(RECV_PIN);

decode_results results;

void setup()
{
Serial.begin(9600);
irrecv.enableIRIn(); // Start the receiver
}

void loop() {
if (irrecv.decode(&results)) {
Serial.println(results.value, NEC);
irrecv.resume(); // Receive the next value
}
delay(100);
}

Your compiler is picking up the built-in RobotIRremote library rather than the third-party library you should have installed. The built-in library used the Robot pin names which are different from the UNO pin names/numbers. Did you install the IRremote library? Unless you have a (now obsolete) Arduino Robot Control Board you can safely delete the Robot libraries from C:\Program Files (x86)\Arduino\libraries\

What libraries should i install?

And what should i delete? I deleted all the robot libraries and i got another error

Cuirithir:
What libraries should i install?

The IRremote library since that is the library you are trying to use. Google can help you find it.

Cuirithir:
And what should i delete? I deleted all the robot libraries and i got another error

I'm going to guess that the 'other error' has something to do with the IRremote library. Perhaps it says "IRremote.h, file not found" or words to that effect.