[Windows Phone 8 Development and Hacking] TheIronMaiden:
Thanks to http://forums.windowscentral.com/members/pankaj981.htm

Description

This guide will show you how to impersonate another device and get WP 8.1 Update 2 (OS version 8.10.15137.148)

Warning:

1) Changes made to your phone are not permanent and can be restored using Lumia Software Recovery Tool or Windows Phone Recovery Tool

2) I would not be taking responsibility if you accidentally brick your phone so please ask questions before proceeding

Software Requirements:

1) **Any Nokia Lumia running OS version 8.10.14219 or higher. If you are on a lower version please check for updates from your carrier/Microsoft or update using Preview for Developers

2) Start with a clean software, i.e. reset your phone before proceeding (make sure Preview for Developers is not installed)

3) Files Needed ** I do not own these files. They were linked from this thread **

a) SDK 8.1 Lite.zip (*** install this after download ***)

b) CustomPFD_0003.xap

c) CustomWPSystem_0500.xap

Link: http://xdaforums.com/windows-phone-8/development/xap-customwpsystem-patch-xaps-wpsystem-t2975419

Hardware Requirements:

1) ** Nokia Lumia with SD card capability

2) microSD card

3) USB cable

Process: Part 1 - Preparation

1) Hard reset phone using hardware key combination (Reference)

2) Go through setup process, update all system and preloaded apps

3) Storage Sense >> phone >> apps+games >> select all >> uninstall all apps

4) Storage Sense >> Store new apps on my "phone"

5) Connect phone to PC using USB

6) PC >> Start Menu >> Programs >> Windows Phone Developer Registration >> Register >> Enter MS Account >> Done >> Close

7) PC >> Start Menu >> Programs >> Windows Phone Application Deployment 8.1 >> Target = Device; App = "pathoffile\CustomWPSystem_0500.xap" >> Open >> Deploy >> Deploying File >> App deployment complete. >> Close

8) Verify if CustomWPSystem shows up in app list

9) PC >> Explorer >> My Computer >> Select Phone >> SD Card >> Documents >> Move CustomPFD_0003.xap here >> Done

10) Storage Sense >> Store new apps on my "SD Card" >> Done

11) Store >> Download Preview for Developers >> Let it install >> Don't open after install >> Pin to Start >> Done

12) Open CustomWPSystem >> Click on red bar "SD Card permissions" >> Select "sd card" >> Press "done" (check mark below) >> red bar turns green

13) Scroll down under "Modding selected app", select "Select the XAP" >> Phone >> sd card >> Documents >> Select "CustomPFD_0003.xap" >> Apply XAP >> Wait till you see popup "Operation completed!...." >> Done >> Close app

Process: Part 2 - Registry Edits

1) Open previously pinned Preview for Developers app >> HKLM >> SYSTEM >> Platform >> DeviceTargetInfo

2) Edit Registry:

** Note down the registry keys before editing them. To avoid resetting, revert back to default registry entries and skip 4) **

PhoneMobileOperatorName >> 000-88 >> Write

PhoneManufacturerModelName >> WinWin >> Write

PhoneManufacturer >> HIGHSCREEN >> Write

** Registry edits are restored to default with hard reset **

3) Settings >> phone update >> check for updates >> Install Updates >> Done

4) Reset after updates are installed >> Start fresh

Source: http://forums.windowscentral.com/wi...stalling-wp-8-1-update-2-lumia-devices**.html