If you've forgotten the password to your windows phone then the easiest mode of regaining access to your phone is to do a hard reset. The first step is to switch off your phone. Now, the exact method might vary with your device but two approaches are:
1. Hold down the Volume up button, then hold down the Volume Down button and then press the power button (briefly) to switch the phone on.
2. Keep holding the volume up and volume down buttons until you see a reset screen option.
3. Now follow the instructions that will show up on your mobile screen to factory reset your phone.
If that doesnt work:
1. Press and hold down the Camera, Volume Down, and Power buttons simultaneously (@ d same time).
2. Release Power when the phone vibrates, but continue to hold down Camera and Volume Down.
3. Release Camera and Volume Down when the Format prompt is displayed on screen.
4. Press WP7 Windows button.
5. Press WP7 Windows button again to confirm the hard reset.
Refer to http://www.windowsphone.com/en-ng/how-to...t-my-phone for other Windows phone types