Admob/Playservice in Android Studio einbinden Error

[amisha]

Hi,
ich habe dieses offizielle Tutorial von Google befolgt um Admob verwenden zu können. Allerdings gab es diesen Error:

Error:A problem occurred configuring project ':app'.
> Could not resolve all dependencies for configuration ':app:_debugCompile'.
   > Could not find com.android.support:support-v4:20.0.0.
     Searched in the following locations:
         https://jcenter.bintray.com/com/android/support/support-v4/20.0.0/support-v4-20.0.0.pom
         https://jcenter.bintray.com/com/android/support/support-v4/20.0.0/support-v4-20.0.0.jar
         file:/Users/Usernam/Downloads/adt-bundle-mac-x86_64-20140702 19-35-51-045/sdk/extras/google/m2repository/com/android/support/support-v4/20.0.0/support-v4-20.0.0.pom
         file:/Users/Username/Downloads/adt-bundle-mac-x86_64-20140702 19-35-51-045/sdk/extras/google/m2repository/com/android/support/support-v4/20.0.0/support-v4-20.0.0.jar
     Required by:
         Appname:app:unspecified > com.google.android.gms:play-services:6.1.71

Ich habe die SDk bereits neu gedownloadet und auch Google Play service und Repository installiert.
Wodurch könnte der Error entstehen?

Danke