Guide for Interop Unlocking your Windows Phone with a microSD card

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While have teased microSD card based interop unlocked a few weeks ago, it is WindowsBlogItalia who has first posted detailed instructions on how to achieve it.

Interop Unlock is a full jailbreak for your Windows Phone, meaning you have access to every file and directory on the handset, and can run any arbitrary code, including .exe apps which can really back up your handset to microSD card for example for restore after a hard reset.

To unlock your handset you need a Lumia with microSD card slot, a microSD card, cable, PC and Visual Studio (the free version will do). Here’s the full guide (translated using a translating tool, and we unfortunately can’t confirm if the translation is 100% correct):

We’ll not be responsible for any damage caused when you try to Intertop Unlock your phone and we don’t recommend following the steps on your daily driver either. 

  1. First – we know that you did not! – you have to read the first four points of the opening of the article: are really fundamental.
  2. Follow the guide linked here to install CustomWPSystem and stop at one installation (remember to install the app in the phone memory and not on the SD card) – make sure you have the version 0.6 .
    • In the guide you linked primarily affects the video , which explains the various steps.
    • Instead of Visual Studio, as stated just above (NEED), you can instead download the abridged version , to save time and space.
  3. Now you need to move the app and Extra info on the SD card: to do this, move the date of your device forward at least 100 years . Then open the app and Extra info (from System Settings) and confermatene removal . Rearranged date. Do not worry about the mistakes of the email app, they will disappear when the date will again be the correct one.
  4. Head for the sensor memory and how to choose the default installation of the app to the SD card .
  5. Download ROMBuilder the link at the bottom of the article. Do not install the app , but just copy it to a folder on your phone (or Documents in the root of the SD card).
  6. Start CustomWPSystem and assign permissions tapping the SD Card permissions : the screen that appears choose the SD card and then the check. For confirmation the button will turn green .
  7. Now you have to choose the target app: Tap on the box with the app (by default you will find Preview for developers) and choose Extras and info .
  8. Click Download from Store and make the download of the app . If you have followed the instructions carefully, the app will be properly installed on the SD card.
  9. Now capped Select the XAP and select the file saved in the phone memory ( ROMRebuilder ).
  10. You just have to click Apply XAP and wait for the end of the procedure. If an error occurs, follow the FAQ in the article dedicated to CustomWPSystem.
  11. Copy the Data folder in the root of the SD card (should be D: \ data)
  12. Download the file data.bin related to your model and copy it in the data on the SD card of your device. If you do not find your device, follow the procedure below to tutorial.
  13. Open and extra info, you will notice that now opens ROM Rebuilder Click “Rebuild”, if “success” the file will be applied correctly
  14. Now you need a hard-reset to apply the change. When you restart your device will have the interop-unlock active!

If you get stuck in paragraph 12 because you do not find the file data.bin for your device, you can follow these steps to create it:

  1. From
  2. Copy the file on the PC and open the reg file with a program that supports the gzip file, in our case we will use7-zip  (not extract).
  3. Archive (always from 7-zip) you will only find a file without an extension, click it and press F4, or choose the option “open with your favorite editor” after clicking the right button.
  4. Open the file with a text editor and add at the end of the file contents of the file that you will find the archive of additional_entries.reg ROMRebuilder and saved
  5. Rename the file