HI
imei null/null can be EFS problem or hardware ..
to repair EFS and Phone not found..
*flash this EFS in PDA
*after flash imei will be 004999010640000 now repair imei & SN and restart your phone will be ok
PHP Code:
Selected model: I9300
Selected port: COM3 Z3X BOX Serial Port
Selected port speed: 115200
Reading phone info...
Model: GT-I9300
Android version: 4.0.4
Product code: Unknown
Phone version: Unknown
PDA version: I9300XXBLH1
CSC version: I9300OJVBLH1
IMEI: null
Phone S/N: Unknown
Checking Super user right... false
Rooting phone, please wait... OK
Checking Super user right... true
Writing EFS to phone... OK
Rebooting phone... OK
Done with Samsung Tool v.15.5
PHP Code:
Selected model: I9300
Selected port: COM3 Z3X BOX Serial Port
Selected port speed: 115200
Searching ADB device... OK
Reading phone info...
Model: GT-I9300
Android version: 4.0.4
Product code: GT-I9300RWDBTU
Phone version: I9300XXLH1
PDA version: I9300XXBLH1
CSC version: I9300OJVBLH1
IMEI: 004999010640000
Phone S/N: RF1C722PVCD
Checking Super user right... true
Reading data from phone... OK
Repairing network settings... OK
Writing data to phone... OK
Rebooting phone... OK
Now connect phone to UART cable
Checking phone at COM3 OK
Reading phone info...
Model: GT-I9300
Country code: BTU
Factory SW: I9300XXBLH1
Unique number: CVTF1E56D2AD46F
Memory phone: VTU00M
Bypass MSL... OK
Repairing IMEI... OK
Repair done
Rebooting... OK
Done with Samsung Tool v.15.5