how to upgrade iphone5 ios7.1 to 8.1.2 now

[CrownClit]

hi need some instructions or tool recommendation to performs this upgrade.
current ios ver is 7.1 need to upgrade to 8.1.2 not any higher.
I have read lots on net but most docs will use standard options and upgraded to latest 8.3 which is no good for me.
I have copy of 8.1.2 on my win pc. using win 8.1 x 64, itune 12.1.2.27

could someone please help me out?


CC

[freakee1]

if apple isn't signing iOS 8.1.2 then you have no chance

in a previous life when Shsh were of some value you could trick the phone to think it was ok to upgrade - downgrade. Apple have released 8.3 and that's all they would be giving approval for

check out






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