3GS upgrade, downgrade, original sim, cydia........VERY CONFUSED

[harshunlimited]

Device: iPhone 3GS
Current OS: 3.1.2 (7D11)
Modem Firmware: 05.11.07
Jailbroken with: blackra1n (tethered)
Carrier Unlocked
PC OS: Win 7 & XP
Location: India

Do NOT have original ATT sim, but have ordered 1 from ebay.

Is there a way to ckeck whether the sim is working or dead before I start the upgrade process? I don't want to stuck at that.

What I would ideally want is to upgrade to ios 4 and jailbreak (using jailbreakme) & unlock (ultrasn0w). Is it possible? if yes, how? if not, then how to get an untethered jailbreak & unlock.

Although I have 3.1.2 on my 3gs, the cydia says it has SHSH for 3.1.3, 4.0, 4.0.1 for this device. Does this mean that I should restore to 4.0.2 using itunes & official apple and then be able to downgrade to 4.0.1?

What I have understood till now is the following steps:

1. Restore the device to 4.0.2 using itunes.
2. Using Cydia & Tiny Umbrella downgrade to 4.0.1
3. Insert the ATT sim, go to jailbreakme.com on device safari.
4. Go to Ultrasn0w for carrier unlock.

Are the above steps right?

It is all very confusing reading all these jargons, please help, since at least 8 of us (including me & my friends) here in India will be benefited from this reply.

[MindGem]

Why restore to 4.0.2?

[harshunlimited]

okay, directly install 4.0.1? and all the other steps looks fine?

how to check the sim card?

[Will13]

Yes just download the 4.0.1 firmware, and shift+click restore in iTunes, but I dunno about sim, since it will say no service

[Simtech]

Save your 4.0.1 SHSH files ASAP. I am sure apple will quit signing that firmware soon.

[harshunlimited]

Save your 4.0.1 SHSH files ASAP. I am sure apple will quit signing that firmware soon.

@simtech : Apple has already stopped signing the firmware, but although my device has 3.1.2, when I open cydia, it says SHSH saved for this device for 3.1.3, 4.0, 4.0.1. doesn't it mean,saurik's server will now sign it?

[jkmonkey]

@simtech : Apple has already stopped signing the firmware, but although my device has 3.1.2, when I open cydia, it says SHSH saved for this device for 3.1.3, 4.0, 4.0.1. doesn't it mean,saurik's server will now sign it?

No, apple has NOT stopped signing 4.0.1. I just checked with umbrella directed to apples server and it retrieved shsh's for 4.0.1.

[harshunlimited]

then I ll just have to wait till I get my sim ordered on ebay, bought it on 13th, the seller says should reach within 5 - 10 days

Apple has stopped signing 4.0.1 and 3.2.1 SHSH requests for all devices now.

Source : The Firmware Umbrella

Now, what should I do?

[harshunlimited]

Okay, now my ATT Sim has arrived, for last time, please reply my queries (you may say YES or NO, if not a one liner reply):
1. Currently my 3GS has 3.1.2, cydia says it has "shsh for 3.1.3, 4.0, 4.0.1 for this device". Does it mean that I can upgrade to 4.0.1? now since apple has stopped signing.
2. If above yes, should i first restore to default factory settings (since it is now JB with blackrain) or simply shift + restore and upgrade to 4.0.1 (i have .ipsw downloaded)? Would I need to change host file to gs.apple.com?
3. Since, the bootroom is new, would I be able to unlock on ultrasnow and use it with my indian carrier?

Please do try and help me.

[jkmonkey]

Yes, since you have shsh's on file you can upgrade to 4.0.1. Moddify your hosts file to direct to cydia's server then shift+click restore to 4.0.1. Use jailbreakme to jailbreak then install ultrasn0w from cydia to unlock.

[Trooper Sam]

And don't forget the PDF patch.

Also, I've heard that you should remove the mods to the HOSTS that redirect to Cydia. However, I don't really see why that would be necessary. If it's a firmware that Apple is signing, Cydia will pass the request through and save the SHSH. If it's not being signed but it's saved on Cydia, Cydia will return the SHSH you've saved.

[harshunlimited]

Thanks to all you guys out there, I got my phone working on 4.0.1 with unlock successfully, my worst fear about sim came alive, it did not work, was stuck on emergency calls only & enter a valid sim (on itunes) screens, but luckily a friend had a one sim, activated through that......once again sincerely thank you....cheers!!