Upgrading Galaxy S2 · DIGIT-ARC

Yesterday I tried upgrading my Wife's Galaxy S2, who is still using old Gingerbread. Twince it happened, that it download 218 MB, restarted and then dispalyed error message "Failed to upgrade firemware, either use Samsung Kies or contact service center". Can someone help me in resolving this issue?

This is an indian firmware. My mom also owns a Galaxy S2 but purchased from 3UK. Almost an year ago I successfully upgraded it to ICS and last night upgraded it to Gelly Beam. But with this indian version there are always issues. It never showed in Samsung kies about any available firmware upgrade almost an year ago when my mom's S2 was successfully upgraded to ICS.

factory reset the mobile and check if KIES shows any update being available. You can always flash the official release through ODIN but won't recommend that. Not safe.

before factory resetting. How can I upload the contacts in Cloud so that i can restore them laster from Cloud?

Sync it with Google account

if you can access play store, the contacts are already sync'd. just to be sure, visit Google Contacts while being logged in with the email id used when the mobile was first registered with google.

Search the Play Store for contacts backup app. Backup to SD card.

Then, use ODIN to flash an international version of S2 upgrade. Don't bother with the Indian version of ICS.

maverick786us said:
before factory resetting. How can I upload the contacts in Cloud so that i can restore them laster from Cloud?

In Android, all Contacts get synced with your Google account by default.

Just to be sure, go to Settings --> Accounts and sync --> click the Google account and then tick Sync Contacts --> Sync Now.

I upgraded my mom's Galaxy S2 to jellybeam. Now it is asking for Network Sin Unlock Code

Is there a way I can revert it back to ICS? Can someone give me a link from where I can download unlocked firmware of UK and flash it? Can someoen also provide me instructions to flash it?

maverick786us said:
I upgraded my mom's Galaxy S2 to jellybeam. Now it is asking for Network Sin Unlock Code

Is there a way I can revert it back to ICS? Can someone give me a link from where I can download unlocked firmware of UK and flash it? Can someoen also provide me instructions to flash it?

Stop using Samsung Keis... Just use ODIN to flash the International version of Jellybean, or better yet, Cyanogenmod 10. Stop using Keis.

See thread [ROM][GT-I9100][JB][4.1.2] CyanogenMod 10 official nightly builds - xda-developers

Also, maybe this can help you -- [17/02/2013][TOOL] Samsung Network/Sim Unlock Code Generator/Patcher (SGS1/2/3) - xda-developers

AndroidFan said:
Stop using Samsung Keis... Just use ODIN to flash the International version of Jellybean, or better yet, Cyanogenmod 10. Stop using Keis.

See thread [ROM][GT-I9100][JB][4.1.2] CyanogenMod 10 official nightly builds - xda-developers

Also, maybe this can help you -- [17/02/2013][TOOL] Samsung Network/Sim Unlock Code Generator/Patcher (SGS1/2/3) - xda-developers

No I didn't use Samsung Kies. I directly upgraded my mom's Galaxy S2 to jelly beam on air. Now looks like its locked. My only option is to jailbreak it or flash a firmware that is UNLOCKED. Almost an year ago I upgraded my mom's GS2 to ICS. That time it didn't lock, so I thought its not a jail broken device. But after upgrading to JB it got locked