Auth.startOAuth2Authentication. Android returns "... User may have restricted profile"

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I'm adapting code from https://github.com/dropbox/dropbox-sdk-java/tree/master/examples/android to allow my photo-saving app to directly store files into Dropbox. I think I've managed to add the various libraries and functions that are required. However, when the app attempts Dropbox authentication on startup, the following error is returned:

---.---.stdb E/com.dropbox.core.android.AuthActivity: Could not launch intent. User may have restricted profile
    android.content.ActivityNotFoundException: No Activity found to handle Intent { act=android.intent.action.VIEW dat=https://www.dropbox.com/... }

It looks like the issue is related to "User may have restricted profile".

What's going on?