The first of Windows Phone 7 unlocking tool is released within days after its launch. Rafael Rivera, Long Zheng and Chris Walsh have released a tool called ChevronWP7, which allows you to lock Windows Phone 7 without the need for a Marketplace account. Unlocking allows the test experimental applications that would otherwise can’t be published to the Marketplace, such as those which access private or native APIs.
ChevronWP is a simple exe file which will allow anyone to unlock any WP7 device on the market using a USB cable and just a couple clicks. This tool is completely safe and reversible for the phone. (The app even allows you to relock the phone.)
To unlock the phone, you need to connect the phone to your PC using the USB cable and then run the Zune software. Now run the exe file and you can unlock your Windows Phone 7.