first of all write the all probs which u r facing in the phone and write have u done something wrong in the phone.
dial it *#7780# in the phone. Simply enter the sequence and it will begin restoring the ini files in your phone.
If the trick does not work then try the following method.
1. Switch off your phone.
2. Press and hold the three keys, green or talk, 3 and * together.
3. Release the keys only after your phone starts up.
Luckily, this solution may prove worth to you and restore all the lost files.
This method also works for the phones that dont switch on.