Why am I unable to factory reset Windows Phone devices?

[michael_holls]

Unable to factory reset Windows Phone devices

Hi All,

The company that I work for are rolling out Windows Phones. When we have been testing the devices, we want to wipe the device and start fresh to check changes work. Since one of the policies we apply to the phone blocks the ?reset phone? button in the settings menu we used the boot loader method (This does not affect it as I still cannot get the device to wipe on a fresh image).

This method worked fine for me with my Microsoft Lumia 640 LTE however some of our other phones aren?t working that way.

When attempting the procedure by holding the volume down key, the exclamation mark doesn?t appear and the phone just power cycles. If we boot holding the volume up key then the phone will go to a screen similar to the exclamation mark but the exclamation mark is replaced by a lightning bolt and a cog. I cannot find much information about this online so any help would be appreciated.

Devices struggling with:

• Nokia Lumia 735 - WP 8.10.15148
• Microsoft Lumia 535 - WP 8.10.14234
• Nokia Lumia 735 - WP 8.10.14219
• Nokia Lumia 625 - WP 8.10.14219

Devices successfully wiped:

• Microsoft Lumia 640 LTE - WP 8.10.15148

 

[mjperry51]

Re: Unable to factory reset Windows Phone devices

Do your policy settings disable the "Reset your Phone" in Settings| About Phone??

 

[michael_holls]

Re: Unable to factory reset Windows Phone devices

Unfortunately it does to prevent users accidentally wiping the device.

 

[Torcher Death]

Re: Unable to factory reset Windows Phone devices

Well, if hard reset doesn't work, then maybe try the recovery tools ?

 

[michael_holls]

Re: Unable to factory reset Windows Phone devices

I am going to try the recovery tools tonight but the corporate PCs annoyingly block USB devices which is why we wanted to know why we don't seem to be able to wipe the devices using the hard reset.

 

[Torcher Death]

I've had that lightning bolt with cog symbol shown a couple times while doing hard resets... but powering down the device & just leaving it to charge for 5-10 mins & rebooting has solved it in the past.
As for whats causing the issue, am equally clueless.

 

[michael_holls]

Thank you for all your answers. We are resorting to the Windows Device Recovery Tool as it appears that the MDM must alter the boot loader to prevent access to this area as we can access the area after factory resetting. The policy must go deeper than we thought!

Thanks for your help though.