Project refresh failed Error:exception during working with external system: - Android Studio 2.1 Preview

I updated the Android Studio to Preview 2.1 and the gradle is updated as well

dependencies {
    classpath 'com.android.tools.build:gradle:2.1.0-alpha1'
    classpath 'com.google.gms:google-services:2.1.0-alpha1'
}

I got this message :

When i click on the Try Again shown upside, i get this message

Gradle 'TestProject' Project refresh failed
  Error:exception during working with external system: 

Anybody faced and solved this problem ?