Android GCM sent successfully but not received on some devices

Question

On the server side, I am using GCM server 1.0.2 library provided by Google. On the client side, I set up GCM as provided on the official documentation.

My problem is

Answer 1

Checklist

• Make sure Google Play Store is updated to latest version
• Make sure there are no systemwide settings for notifications which are blocking
• Go into app in Application Manager and uncheck/recheck 'Notifications'
• If on Wifi, switch Wifi connection to a different AP (if possible)
• Reboot the device
• Install 'Push Notification Fixer' (install this anyway)

First-run notification setup can be annoyingly arbitrary and require the device be 'kicked' in one or more of these ways.