This is a reminder that effective January 1, 2015, it will no longer be possible to unlock Windows Phone 7.x devices for app testing.
So if you have a Windows Phone 7 device, we recommend that you developer unlock your Windows Phone 7.x devices prior to January 1, 2015 in order to continue testing your apps with those devices.
Please note this unlock will be good for 24 months.
On January 1, 2015, if you have not unlocked your Windows Phone 7.x device, deploying and testing of apps from Visual Studio on that device will no longer be possible.
Please note that this change will not impact apps available in the Windows Phone Store, nor will it impact customers with Windows Phone 7.x devices.
Additionally, if you have apps that only have a Windows Phone 7.x package, now is a good time to update these apps to Windows Phone 8 or 8.1.