Release Android phone that has lost contact

Hi!

We have only a few Android devices in our organization (but lots of iOS/iPadOS devices) and most of the Android devices are for special purposes, which means that they really don't notice if they loose contact with the ZENworks server. We also kind of missed the Google FCM API changes, but I think I fixed it now. At least a few Android devices has refreshed since I reconfigured FCM.

However, I have a Samsung in a drawer for testing purposes, I haven't used it for a year or so but yesterday I got it out to test something. Of course it won't talk to ZENworks. Not only has the Google FCM API changed since I last used it, the MDM server certificate has also been reminted recently. The ZENworks app on the phone says "The Device Certificate is not valid. Please contact your administrator". The device policy that was applied to it is quite loced-down, it doesn't allow factory restore, removal or inactivation of ZENworks app or anything that could release the device from management. Is there any way to wipe the device or otherwise overrun the policy that still applies but cannot be managed from ZENworks now. I tried adding the new MDM server certificate in settings, but that didn't help. It is perfectly fine to wipe the device completely, by force if needed. If there is a way to do this it cuold be useful for re-registering other Android devices that has lost contact.

Kind regards

Bengt

  • Verified Answer

    +1

    You might be able to reset this phone by booting into recovery mode.

    These instructions work to get into recovery mode on Samsung Tablets so may work on a Samsung phone too:

    Boot in to recovery mode. Follow this procedure:

    1. Press the "Power" and "Volume down" buttons simultaneously until "Switch off" and "Restart" appear on the screen.

    2. Press the red "Switch off" symbol on the screen and confirm again. The tablet shuts down.

    3. Connect the tablet to a PC with a USB-C cable and wait until the final battery level is displayed in percent (the percentages count up and the circular ring around the battery level becomes brighter and brighter). You cannot enter recovery mode without USB-C cable connected

    4. With the tablet still switched off and connected to USB-C, press and hold the "Power" and "Volume up" buttons until you see the Samsung splash screen.

    5. In "Recovery Mode", the menu items can be selected with the "Volume up" and "Volume down" buttons and confirmed with the "Power" button.

    6. Choose "Wipe data/Factory reset"

  • 0 in reply to 

    Hi!

    This actually worked! Really big thanks, Matt!

    Kind regards

    Bengt