Hi, I recently bought this handset n couldnt use the phone as it displays on the screen " Invalid IMEI " with no signal on the top when any sim is inserted.Phone does display the sim no. n relevent internet settings.I spoke to my network provider n they gathered as the phone beeing locked.I have rest it once at the advoice of the seller but without any luck.I decided to give it a try on this forum to find any solution before I send it back. Can anybody help me with some solution to fix this problem?Thanks