Failed to initialize Vuforia

Hi,

I have a brand new install of Android Studio 3.1.2 on Mac.

Wikitude is compiling and running perfectly fine.

I have:

VuforiaSamples-7-1-34 vuforia-sdk-android-7-1-34

I put the example in the samples folder and opened the project in Android Studio.

It compiles and runs on my LG G6 running Android 7.0.

The app loads but all the demos crash and say:

Failed to initialize Vuforia

I have tried to change the SDK target but it doesn't make any difference.