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4.2.1 help


New Member
Dec 12, 2010
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Im trying to unlock my Iphone4 and Im having a hard time doing it, any help would be great.

My question is can you downgrade from 4.2.1 back to 4.0?

I did a search with the search tab and I didnt find anything so I thought I would ask. I need to have it done by tomorrow thats when my new sim cards will be here, I'm completely lost and I really need help.

I have downloaded the redsnow application but it was a zip file so Im not sure if that is correct. I've tried watching videos on youtube and I guess Im just not fast enough to figure it out.

Everyone says it should be simple but Im having serious issues.

I use windows 7 also.

I've tried jailbreakme.com and it says I need to try to downgrade so is that possible?

Thanks in advance for any help that anyone can offer
You can downgrade the firmware from 4.2.1 to 4.0 if you have SHSH's saved for that firmware. If you don't know what that is then you won't be able to downgrade.

Even if you have your SHSH's and are able to downgrade to 4.0 you still can't downgrade the baseband so you won't be able to unlock anyway...