i have galaxy s2 working fine with android 4.0.4 am trying to update to 4.1.2 using stock rom
but when i try to enter download mode this screen come up>> PLEASE HELP
So you do not have Download Mode. Thats very confusing. So far as i know Download Mode is embed in Secondary Bootloader and it lookss like SBL has a problem with starting Download Mode. So maybe you need to replace SBL? Its very risky but when you flash stock rom it will happend anyway. Maybe you can try that manually. As long as you dont have access to Download Mode you cant flash rooted kernel but maybe you can flash it from Recovery Mode as update.zip
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