please i have a similar problem. I recently bought this samsung galaxy s3(AT&T) from a friend. when i started using it, i notice it does not see network when am inside any building, so i thought of getting an appilcation that would boost the signal strength. I bust into this app called arizapatch online for reviving network. i downloaded it and followed all the process for it installation. After the installation, it ask me to reboot which i did. Sadly, the phone is not just booting again. it says "could not do normal booting" and some other stuff. I tried to flash the rom (because i can boot into download mode ) with various firmware i got from sammobile using odin. But Odin keeps failing during the flashing process. I dont know what to do again and this is really frustrating me. Please, any advice, suggestion or recommendation would be highly appreciated.