Here are some ways which you can simply reset/restore your phone to default settings if your phone is hanging or restarting or malfunctioning.
Press *#7780# or *#7370#, then enter your password or enter Nokia default password which is 12345
Press *#7780# or *#7370#, then enter
Your password (just like java phone) but there some times that, you won’t be able to press the above codes due to the fact that your phone restarts quickly. So what you need to do is, switch the phone off, hold down the green button, then hold down 3key and hold star key (*) now turn the phone on. Wait till it shows a screen asking you to select country. You have successfully format the phone. Note that this hard reset doesn’t format your memory card.
Press *2767*3855# or switch it off, hold the “Down Volume Key” now power it on. Use the volume key to navigate and use the power to select
Press *#311# or *#*#7378423#*#*
Windows Mobile phone
Sprint: Touch – Hard reset is done by holding the green and red buttons and then pressing the small button beside the USB plug Motorola Q9c – Power on holding the center button and it will ask you if you want to hard reset..
Mogul: Hold soft keys while pressing reset button on the side
Verizon Motorola Q : Power on holding the center button and it will ask you if you want to hard reset.
Motorola Q9M: Power on holding the center button and it will ask you if you want to hard reset.
Blackjack: Just power on holding up on the DPad and it will ask if you want to erase all data. Press 1 to erase and y to confirm
Cingular 3125: Go to Accessories in the Start menu and select Clear Storage. If you can’t access the menu turn off the phone, and hold both soft keys while powering on.
Motorola Q9 Global: Turn on the phone while holding the E and Z keys.
AT&T Tilt: While holding down the two soft buttons on the front of the phone (above the Windows and OK buttons) press the reset button with the stylus for a second.
Palm Treo 750: While holding the red “end-call” button press the soft reset button next to the mini-SD card slot for a second or two.