Windows Phone 7 ‘calls home’ to re-lock ChevronWP7 unlocked devices

By Tom Warren, on 8th Dec 10 8:19 am with 1 Comment

Windows Phone 7 ‘calls home’ to re-lock devices that aren’t authorized to be unlocked.

Devices that have taken advantage of the ChevronWP7 unlock will be re-locked periodically, thwarting attempts by homebrew developers. Microsoft has a built-in method that checks the device IDs of Windows Phones against those on a server. The method is used to re-lock official developer devices after a Windows Phone 7 developer closes his or her developer account. Microsoft periodically checks if a device is registered as a developer device and should remain unlocked.

The developers of ChevronWP7 confirmed the lock in a blog posting on Tuesday. The ChevronWP7 team confirmed they were warned by Microsoft that after a short time, approximately two weeks, phones unlocked by ChevronWP7 would revert back to their original state. “Contrary to circulating reports, Windows Phone 7 devices unlocked via ChevronWP7 are not being targeted by Microsoft. Instead, the phone is reverting back as a result of a periodic check” writes Rafael Rivera, ChevronWP7 developer.

The revelations of a “re-lock” are a big blow to homebrew applications using the ChevronWP7 unlock method. Applications side-loaded onto the device will fail to launch after the device is re-locked, simply stating the application has “been revoked by Microsoft please uninstall it”. Users are presented a button to uninstall the application.

The tool, released less than a week ago, was the first “unlock” for Windows Phone 7 that allows owners to side-load applications, usually only reserved for official Windows Phone developers. ChevronWP7 unlocked the sideloading of experimental applications that aren’t published to the Marketplace. Applications that use private or native APIs are denied from the Marketplace but ChevronWP7 allowed these to be side loaded without the $99 cost of a developer account.

Despite Microsoft asking the ChevronWP7 team to remove its “unlock” for Windows Phone 7, eager developers are still working on homebrew applications for Windows Phone 7. Windows Phone 7 developer, Tom Hounsell, confirmed to WinRumors last week that he is currently coding a homebrew IRC application. A Google Maps homebrew application has also been released.

Microsoft is currently engaging in discussions around officially facilitating homebrew development on Windows Phone 7 according to the ChevronWP7 team.

  • Sandra Chung

    All this does is make you re-run the unlocker when you want to install something. Doesn’t stop a durned thing.