1.Connect the phone in fastboot mode .(fastboot/adb drivers must be installed)
2.download the philz recovery here . now install this recovery as boot file by typing 'fastboot flash boot philz.img(i.e. whatever the name it has)'
3. download the backup file and radio from here http://forum.xda-developers.com/xper...peria-t2963316
4.copy the clockworkmod folder to your sd card , now i hope u'll be able to boot into recovery. booting into recovery go to backup and restore , go to the last option that'd be of some setting and in those setting uncheck the option md5 check and then go to restore from sd card and select the only backup. after backup install the radio then, i hope u will be able to get your phone as it was earlier.
5. if u get recovery but get issues with the backup or running the stock rom, install the cm12.1 from here http://forum.xda-developers.com/xper...-12-1-t3071012
Hope it works