For Windows Phone users, the Windows 10 is a major upgrade. The new OS is supported by devices with 1 GB RAM and above, such as the Lumia 730, Lumia 830, Lumia 930, Lumia 1520, Lumia 640, Lumia 640 XL and a few others. However if your device is not listed you can try it by following this tutorial. Do not follow this process on devices with 512 MB RAM. I first stumbled upon this tutorial on XDA forums.
Step 1. Join Windows Insider program here, https://insider.windows.com
Step 2. Install Windows Insider app from the Store.
Step 3. Start “Windows Insider” app, select “Get insider build”, now decide the way updates are delivered, you will get 3 options: Insider fast, Insider slow, and Production ring. If you want to play safe, select the last option.
Step 4. Now check for phone update in your settings, the download will begin shortly. Once it’s downloaded it will prepare to install and when ready, you need to select restart now. It will show gears spinning and when it’s over, you are already on Windows 10 Phone.
The Windows 10 phone version you install will be the Threshold 2 build. If your phone is not able to get “Windows 10 Phone (Redstone build)” with “Insider Fast configuration”, your phone is not getting it any sooner. Not all phones will receive the Redstone build. However, it is possible to try out the Redstone builds on older devices for the cost of some minor issues such as glance screen not working.
Upgrade from “Windows 10 Phone (Threshold 2 build)” to “Windows 10 Phone (Redstone build)” on older unsupported devices
Step 5. Go to settings -> Update & security -> For Developers -> Enable the Developer mode here.
Step 6. Install the provided Interlop tools appx file along with its dependencies on your phone from file manager.
Step 7. This Step Involves Editing Registry Values (NOTE: Do not mess with registry values unless you know what you are doing)
Start Interlop tools -> go to Registry Browser -> HKEY_LOCAL_MACHINE -> SYSTEM -> Platform -> DeviceTargetingInfo ->
Here you have to edit 4 registries- (write the changes)
- change ” PhoneManufacturer ” = MicrosoftMDG
- change ” PhoneManufacturerModelName ” = RM-1085_11302 (for Single SIM devices) and RM-1116_11258 (for dual sim devices)
- change “ PhoneModelName “ = Lumia 950 XL (single SIM) or Lumia 950 XL Dual SIM (for dual SIM)
- change ” PhoneHardwareVariant “= RM-1085
Step 8. Once you are done with writing the 4 values to registry, simply close this app and start Windows Insider app, select Insider Fast, phone will restart. Checking for updates will start downloading Redstone build on your phone, it will upgrade and you are ready to try it out.
A Hard reset is recommended for smoother experience after upgrade. If your device faces connectivity issues, consider doing a reset again.
We have tried installing Redstone build on a couple of unsupported phones such as Lumia 1020, Lumia 920 and Lumia 925. All are working perfectly normal except for the glance screen.
If you need further clarification, hit the comment section.