Configuring a Lumia for Flight Signing

In this article we will discuss how to configure a Lumia for Flight Signing . 

 As of 2017, the old Windows Insider application has been shut down, and thus hacks are required to enable Flight Signing on devices. 

 Preparations 

 
 WPinternals must be installed on the target computer with the resources to unlock the phone bootloader prepared. 

 OSFMount must be downloaded in order to modify a partition. 

 A copy of the SbcpFlightToken.p7b must be downloaded. 

 
 Bootloader Spec A 

 Primary method (Easiest) 

 
 Unlock the device using WPinternals. 

 Go to mass storage mode 

 Paste the token file into EFIESP\efi\Microsoft\Boot\policies\ 

 Reboot the phone 

 
 Alternative method to not cause issues with delta packages (CBSU/SPKU) 

 If you do not want interferences with updates caused by a patched mobilestartup.efi file, you can proceed to the following: 

 
 Unlock the device using WPinternals. 

 Go to the dump section of WPinternals, select the path to your device FFU file. 

 Select a destination path for the EFIESP partition. 

 Dump 

 Mount the EFIESP.bin file you just dumped via WPinternals via OSFMount (make sure you disable read only and use Direct writing mode) 

 Paste the token file into EFIESP\efi\Microsoft\Boot\policies\ 

 Unmount EFIESP.bin via OSFMount 

 Go to the flash section of WPinternals 

 Scroll down to the flash partition manually area 

 Select your modified EFIESP.bin file 

 Flash 

 Reboot the phone 

 
 Bootloader Spec B 

 
 Go to the dump section of WPinternals, select the path to your device FFU file. 

 Select a destination path for the EFIESP partition. 

 Dump 

 Mount the EFIESP.bin file you just dumped via WPinternals via OSFMount (make sure you disable read only and use Direct writing mode) 

 Paste the token file into EFIESP\efi\Microsoft\Boot\policies\ 

 Unmount EFIESP.bin via OSFMount 

 Go to the flash section of WPinternals 

 Scroll down to the flash partition manually area 

 Select your modified EFIESP.bin file 

 Flash 

 Reboot the phone