Many users have been reporting problems with updating their new Window Phone 7 devices. Some users have even reported that their devices have been becoming bricked while they are updating.

To update your Windows 7 Phone follow the procedures below:
Step 1. Make sure you have a charged battery at at least 50%.
Step 2. Connect your phone to a power source other than your computer.
Step 3. Turn your device off.
Step 4. Turn your phone on by holding/pressing the camera, volume up, and power button at the same time, while ignoring any prompts to format your SD Card.
Step 5. Once your phone enters download mode, you can let it sit and reinstall the OS. This will happen over your network and should take around 15 minutes.