Can you show me flashing log? Are you sure that it's C5303 not C5302 and you are using S1 EMERGENCY mode and connecting testpoint properly?
I used flashtool to flash it i don´t know where it saves logs but here is setool´s identify log before all
15/04/2015 04:32:55 p.m. RUNNING v 1.1411/01.15/UNI
15/04/2015 04:32:55 p.m. CARD SERIAL 001xxxxx15/04/2015 04:32:55 p.m. USBFLASH DRIVER VERSION 03.00.00.0015/04/2015 04:33:11 p.m. SIGNED MODE (USING SERVER)15/04/2015 04:33:11 p.m. CFG:10000000000015/04/2015 04:33:12 p.m. PLEASE ATTACH TURNED OFF PHONE NOW15/04/2015 04:33:12 p.m. PRESS AND HOLD "BACK" OR "VOLUME DOWN" BUTTON ...15/04/2015 04:33:20 p.m.15/04/2015 04:33:20 p.m. RUNNING S1_BOOT VER "R11B023"15/04/2015 04:33:20 p.m.15/04/2015 04:33:20 p.m. ACTIVE_COMP_AID : 000115/04/2015 04:33:20 p.m. HWCONF_AID : 000115/04/2015 04:33:20 p.m. LOADER_AID : 000115/04/2015 04:33:20 p.m. BOOT_AID : 000115/04/2015 04:33:20 p.m.15/04/2015 04:33:24 p.m. DEVICE ID: B8CDD10315/04/2015 04:33:24 p.m. FLASH ID: "0000/00000000"15/04/2015 04:33:24 p.m. LOADER VERSION: "R5A058"15/04/2015 04:33:24 p.m.15/04/2015 04:33:24 p.m. PHONE IMEI : 3558100541894315/04/2015 04:33:24 p.m. MODEL (from GDFS): C530315/04/2015 04:33:24 p.m. SOFTWARE VERSION: 1269-3538_12.1.A.0.26615/04/2015 04:33:24 p.m. CUSTOM VERSION: 1271-7710_R2B15/04/2015 04:33:24 p.m. FILESYSTEM VERSION: GLOBAL-LTE_12.1.A.0.26615/04/2015 04:33:24 p.m. SERIAL NO: YT910CP1BK15/04/2015 04:33:25 p.m. Elapsed: 14 secs.15/04/2015 04:33:29 p.m. SIGNED MODE (USING SERVER)15/04/2015 04:33:29 p.m. CFG:10000000000015/04/2015 04:33:29 p.m. Will backup GDFS now.15/04/2015 04:33:29 p.m. PLEASE ATTACH TURNED OFF PHONE NOW15/04/2015 04:33:29 p.m. PRESS AND HOLD "BACK" OR "VOLUME DOWN" BUTTON ...15/04/2015 04:33:35 p.m.15/04/2015 04:33:35 p.m. RUNNING S1_BOOT VER "R11B023"15/04/2015 04:33:35 p.m.15/04/2015 04:33:35 p.m. ACTIVE_COMP_AID : 000115/04/2015 04:33:35 p.m. HWCONF_AID : 000115/04/2015 04:33:35 p.m. LOADER_AID : 000115/04/2015 04:33:35 p.m. BOOT_AID : 000115/04/2015 04:33:35 p.m.15/04/2015 04:33:38 p.m. DEVICE ID: B8CDD10315/04/2015 04:33:38 p.m. FLASH ID: "0000/00000000"15/04/2015 04:33:38 p.m. LOADER VERSION: "R5A058"15/04/2015 04:33:38 p.m.15/04/2015 04:33:38 p.m. PHONE IMEI : 3558100541894315/04/2015 04:33:49 p.m. Trim area read done,"E:\SETOOL\v1.1411\gdfs\ta_35581005418943.zip" written15/04/2015 04:33:49 p.m. Phone detached15/04/2015 04:33:49 p.m. Elapsed: 20 secs.
and then flashed this firmware:
C5303_Customized UK_1272-4687_12.1.A.1.205_R8B
thanks