We just recently upgraded and got two identical Razr M (except for case color).
One has absolutely no issue switching from 3G or 4G back to WiFi when getting home. The other stays in 4G and will NOT go to Wifi unless we completely reboot the phone. All settings are EXACTLY the same, except one has Bluetooth on for use of bluetooth in the car. Nothing else is set differently.
Any ideas why only one phone won't connect to our home WiFi unless we do a complete shut down (but the other is fine)???
What a peculiar situation. But hey, it's nothing we can't tackle head on. So, let's jump right in with troubleshooting. First, we want to forget and then readd your Wi-Fi network on the troubled Razr M and test http://vz.to/Vf6lHC . If that doesn't work, please backup your information, perform a hard reset, and test http://vz.to/Poj5E8 . Please keep us updated on results.
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