
Cricket Wireless is still selling a device that can't be upgraded as well, the Nokia Lumia 635. After all, Microsoft still sells a number of devices that run the OS out of the box, and there's even one, the Blu Win Jr LTE, that isn't even eligible for a Windows 10 Mobile upgrade. None of these results are conclusive, as they don't prove that everyone is having the problem or that Microsoft is not allowing any more Windows Phone 8.1 devices to connect to an account. Those all seem to function fine, as long as they're signed in already. We tested out a few other phones that are running older versions of the OS. We were able to turn off Reset Protection by signing into the Microsoft account, and then use that same account to sign into the phone and download apps from the Store. On the Lumia 550, everything worked just fine.

We were also unable to add an account later through Settings. Then, when it wanted a Microsoft account to sign the phone in, it wouldn't even allow us to enter credentials. This brought up the Microsoft account sign-in screen, and it even allowed us to enter a password, but once signed in, it couldn't connect to turn off Reset Protection. When beginning the out-of-box experience, it asked for a sign-in for Reset Protection.

Sure enough, the Lumia 640 wouldn't allow us to sign into a Microsoft account. We tested two phones (yes, there is a limit of how many phones we'll render useless for you at once), one that would reset to Windows Phone 8.1 Update 2 and another that would reset to Windows 10 Mobile more specifically, a Lumia 640 and a Lumia 550, respectively. Hearing these reports, we of course decided to try it out. This problem would also exist if you're already running 8.1 and do a factory reset of your phone through the software. If you've got a phone that shipped with Windows Phone 8.1 and is running Windows 10, you might want to think twice before using the Windows Device Recovery Tool to roll it back, as some users are complaining that after doing so, they are unable to sign into a Microsoft account.
