That is good news for Galaxy S2 I9100G users, the latest Android 4.1.2 firmware also available for download now. Please make sure that the firmware is compatible to your phone model and the firmware is support your region Network. You can check your phones model version at your phones settings> about device. The Galaxy S2 model GTI9100 is different to Galaxy S2 model GTI9100G,so,please refer tutorial here if your S2 model is GTI9100 .
Below is the step by step tutorial how to manually update by flash Android 4.1.2 I9100GXXLSR firmware into Galaxy S2 I9100G via Odin.
For firmware version I9100XWLSD , XW is represent the region or Network code and here is the region code for your reference:
BD = Cyprus, Griechenland
BH = Mitteleuropäisch
CE = Niederlande, Belgien
CP = Finland
DB = Vietnam
DC = Thailand
DD = India
DT = Australien
DX = Indonesia, Malaysia, Philippines, Singapore, Vietnam
DZ = Malaysia, Singapore
JA = Süd Africa
JC = Algeria, Morocco, Nigeria, South Africa, Tunisia
JP = Algeria, Egypt, Iran, Iraq, Kuwait, Morocco, Nigeria, Oman, Pakistan, Saudi Arabia, South Africa, Syria, Tunisia, Turkey
MT = Schweiz
PO = Frankreich
XA = Österreich, France, Italien, Schweiz, Niederlande, England
XB = Dänemark, Schweden, Norwegen
XC = Portugal, Spanien
XD = Croatia, Czech, Hungary, Slovakia
XE = Bulgaria, Estonia, Kazakhstan, Latvia, Lithuania, Russia, Ukraine (Eastern Europe)
XF = Bulgaria, Croatia, Romania
XG = unter anderen Deutschland
XX = Österreich, Belgien, Frankreich, Deutschland, Ungarn, Italien, Spanien, United Kingdom (Western Europe)
XP = Europe (English, German, French, Italian, Spanish, Nederlands, Polski, Portugues and Turkish)
XW = UK, Italy, Germany, France, Australia, Netherlands, Belgium, Switzerland
ZC = China, Hong Kong
ZH = Hong Kong
ZT = Taiwan
Disclaimer: Manually flash firmware into Android phones may void the phones warranty and has the risk that cause your phone brick. Do not unplug the USB connection from PC during the firmware flashing process. Tutorial below is only for your reference and do it on your own risk.
Step 1: Download Android 4.1.2 I9100GXXLSR_I9100GXEFLSR_XEF.zip , then unzip the file. You will get I9100GXXLSR_I9100GXEFLSR_XEF .md5 .
Step 2: On your computer- desktop or laptop, Open Odin 3.04 (Download Odin).
Step 3: Go to settings > Developer Options to enable your phone debugging Mode. Then turn off your phone and then turn your phone in download mode by press (Home+power+vol down) button.
Step 4: Connect phone to the computer and wait until you get a yellow sign in Odin.
Step 5: Add Android 4.1.2 I9100GXXLSR_I9100GXEFLSR_XEF.md5 to PDA.
Step 6: Start flash, sit back and wait a few minutes.
Step 7: Galaxy S2 GTi9100G will automatically reboot once installation complete.