Can I downgrade iPhone 4 from 4.2.1

[Erik S.]

Like it says, can I downgrade my iphone 4 from iOS 4.2.1 to 4.1 if I download the appropriate .ipsw file?

Thanks.

Erik

[iYeow]

Only if you have 4.1 shsh blobs

[Erik S.]

Ok, guess not, since I don't know what you're talking about.

Thank you though.

I just want to Jailbreak. Any word when Limera1n might be avail for 4.2.1

[iYeow]

You have to text message Geohot about the release , if there is any.

[Janet55]

hmm, after Google search, I got these articles:

Jailbreak iOS 4.2.1 iPhone 4, 3GS, iPad, iPod touch 4G with Redsn0w 0.9.6b4 [Guide] | Redmond Pie
Tethered Jailbreak for iPad 4.2.1 on Mac | iPad Help - iPad Help

but after test, seems all are not good working~~

[iYeow]

This redsn0w 0.9.6b4 is even an older version of 0.9.6b6. To be able to use this tethered jailbreak, at 4.2.1, you will lose your unlock.
There is nothing special about 4.2.1, if you want airprint, you will have to sacrifice your unlock, themes, some of Cydia stuffs not ported to it and your jailbreak will be tethered except for devices like 3g , 3gs (oldbootrom).
My advice is don't upgrade to 4.2.1 yet.

[Janet55]

lose the unlock...
hmm, yeah, I think the better should wait and don't upgrade...

[Erik S.]

Well, on AT&T so don't need an unlock (if I understand the term correctly)

That's the prob, didn't think about jailbreaking til after I upgraded.

[iYeow]

Well, on AT&T so don't need an unlock (if I understand the term correctly)

That's the prob, didn't think about jailbreaking til after I upgraded.

Since you just started to do jailbreaking, you have the choice of a tethered jailbreak with some issues on your iphone or no jailbreak at all until a better jailbreak comes out.