Q:

ngFor won't work with "let"

I can get the object to display on the page if I say *ngFor="#test of data", but if I say *ngFor="let test of data" I get Can't bind to 'ngFor' since it isn't a known native property
I still new at this and I don't understand why it won't output to the screen. Any help is appreciated.
forloop.component.ts
import {Component} from 'angular2/core'

@Component({
    selector: 'loop',
    template: `
        <div *ngFor="let test of data">
            {{test.testing}}
        </div>
        `    
})

export class ForLoopComponent{
  data = [
    {
      testing: "1"
      },
    {
      testing: "2"
    },
    {
      testing:"3"    
    }
  ]    
}

app.component.ts
import {Component} from 'angular2/core';
import {ForLoopComponent} from './forloop.component';

@Component({
    selector: 'my-app',
    template: '<loop></loop>',
    directives: [ForLoopComponent]
})
export class AppComponent {

}

A:

You have an older version of Angular 2. Update it to the final version (2.0.0) in your package.json and run npm install again. 

