First, this is the 10-minute YouTube video that gave me the confidence to go forward to flashing the Lumia firmware and by-pass the Reset Protection Key. Committing myself with flashing the firmware with a few success listed does need some confidence. Get an used Lumia 640 costs $20 (Vietnam, 2018, a good battery is a luck).
In the description, you will find most of the resources to flash the firmware. I used some packages to other place to debrand (AT&T). So here is the list:
- Zip/Unzip tool https://www.7-zip.org/: use to unzip the update file
- Lumia Flash Tool (7.3MB): for flash the firmware into the phone and the USB driver
- Lumia Firmware (~1.8GB):
- iutool.rar 3.6MB: to flash the update to Lumia
- Win10 mobile offline updater - 1.6GB. Extract the file using 7z zip and place them into a folder like "Lumia Cabs".
Here is what I did differently:
- Lumia Cabs.7z. Debranding files from xda-developers.
4.7GB WPBLUE.7z- a suite of software for Lumia phone. I don't need to use this resource. But if you want to have look, download this 4.7-GB file from MEGA.nz was a hassle. Password to unzip
Downloading Lumia firmware needs an extra caution. I downloaed a RM-1073 firmware for ATT and flashed to the phone phone to see if I can overwrite the flash, but I could not. The second try is RM-1073, code 059X153.
The second from the top is the firmware for ATT-branded Lumia 640. I succeded by-passing with 059X153 (ended with 7R CV) firmware.
Click in the second line from the top and the firmward (~1.7GB) should be downloaded.