Warning to unlockers: Apple implemented baseband signature check in iOS 4.2.1!

Your post is wrong, there is currently a way to maintain and have a permanent unlocked basement
Ask your carrier, if your in any place other then the US, their unlock it.

Good. Why shouldn't apple do something to try to try and stop unlocking and even jail breaking. It may not be illegal, but it does violate the warranty.

Um, isn't Apple violating federal statutes where the government said jailbreaking and unlocking phones is LEGAL?

@Wayne Williams : Jailbreaking is not considered "criminal", nor is Apple's blocking of it via software updates. Just because something is legal does not mean that prevention of it is illegal.
Real world example: Lets say it is legal to smoke cigarettes in a restaurant in your state. There is nothing preventing a restaurant from being non-smoking of their own choice, and they can ask their guests to leave if if the guest takes issue with it.
Apple's software updates are their updates. They can pick and choose what goes into them, and we can pick and chose not to install them. Yes, this may prevent us from using the AppStore at some point, but that is the risk we take.
There is precedent for this. Video game consoles have updates that prevent exploits, and many times are required to run games. Some games won;t even run until you install the update.

Well I see it this way, if Apple whats to be all Nazi about if fine.
The dev-team will find a way around it, if not there are other options.

I'm pretty sure that it is AT&T that has required locked phones. Apple sells unlocked phones elsewhere and not just in countries where locked phones are illegal. I believe the US legislation only requires operators to unlock phones on request and operators can still charge ETFs for the privilege so locking is still legal.
As much as I think locking phones in the first place should be illegal (it is anti-competitive and operators can still recoup their subsidized hardware costs through reasonable ETFs) I equally think that people should not be screwing around with baseband firmware. There are most likely legitimate reasons for upgrading the baseband such as bug fixes and performance improvements and however clever the jailbreak devs are there could be unforeseen consequences (degraded network performance etc) by keeping people on old
baseband firmware or even modifying it. I'd much rather see all that effort go to lobbying the government to make locked phones illegal outright.

I meant "it" not "if"

The simple answer is to sell your AT&T iPhone, and go to Canada to buy the unlocked version. Personally I think the exclusivity agreement is in it's waning days one way or the other.

Keep going apple/steve, you are driving away people with this crap! I travel overseas a lot and need a local sim card. If you think for 1 second that you will make me cary 2 phones because i can't unlock the iphone, you are crazy! There are plenty of good alternatives out there these days, and none of them have a north korea style dictatorship trying to control them.

Farbod, for a front page article, might want to have a short blurb in the article explaining what a baseband is and why this matters. While experienced jailbreakers know already, people leaning toward Team Jailbreak won't necessarily know.

@Redshirt we already have several guides up explaining what a baseband is. Etc...

@ George99
You're barking up the wrong tree. It's the US carriers that want you locked into their system, not Steve Jobs. It's AT&T that wants you to pay through the nose for roaming overseas; Steve likely could care less. Apple wants to sell phones and they would happily sell you one not locked into AT&T, but if you want the subsidy,
AT&T wants you by the short ones.

Yes there is a solution for this, I had to deal with this problem yesterday while trying to sync my iPhone. The following steps helped me out but it will restore your phone back to stock, it will not be jailbroken. If you do want to jailbreak it there is a way now (as far as google helped me) to jailbreak your phone on ios 4.2.1. This helped me out: 1st- look for your old firmware downloads
windows- go to your computer, local disk (C:), Documents & Settings, (your user name), Application Data (if you cant see this folder make sure to go to tools folder options and make hidden files visible), Apple Computer, iTunes, iPhone Software Updates, and there's your firmware download, if you don't have a file here simply try to restore your phone and download the firmware from Apple.
2-Knowing how to get to your firmware from the step above, go into your iTunes and plug in your phone, make sure your phone is in recovery mode at this point, when in iTunes click restore and alt at the same time, look for the firmware (above) and open that file, it may fail the first few times but keep trying, it will install the firmware and your phone won't be blocked by Apple. **Make sure not to take your phone to Apple or AT&T because when they put your phone on the pc it will show a code, they will fix it for you but your warranty will be voided.

Firmware and baseband are two different issues.

Allyson, not everyone is a regular reader and even some of us who are, like me, don't know what a baseband is.
If possible, an explanatory sentence or two in the same article is really useful and doesn't seem like too much to ask.

"The baseband is essentially the part of your device that controls the antennae. This has everything to do with your service and signal. This is why most unlockers have to be extremely careful when upgrading. If the baseband changes, it can permanently keep them from achieving an unlock. This is the main reason most unlockers tend to favor PwnageTool. It creates a custom firmware bundle for you to upgrade to that doesn’t upgrade the baseband, only the main OS. If you are running on a legitimate carrier and don’t care about unlocking, the baseband it typically less of a concern. Wifi and Bluetooth don’t run on the baseband either, so iPod touch or iPad owners typically don’t have concerns when it comes to new baseband versions." credit to "Everything you wanted to know about Jailbreaking..."

It ia apple's right if they want to lock out jb'n phones. It may not be illegal but it is in violation of a contract that each and every one of you agreed to. Quit crying and be patient. People smatter than you or I will give you your fix.

I had used Tiny Umbrella to keep from upgrading the baseband when I upgraded to 4.1 and sure enough when I tried to upgrade to 4.2.1 the phone locked up in recovery hell. Since I didn't really care about unlocking the phone - I'd just figured originally I'd preserve the option - I took the phone to the local Apple store and they restored and upgraded it for me and no comments were made nor did anyone say anything about my warranty. I had to re-sync everything and reset a host of preferences and re-enter my Comcast and Exchange server data but at least I have a phone again.

Please kids, by all means abandon Apple and go Android. Play on a wannabe phone. Kill off your phone's security. Have a malware party! Enjoy rubbing elbows with the rubbish of the app world.
Seriously: I can see the benefit of hacking to hackers. However, this is excellent news for the security serious. It means there are no more opportunities for drive-by iPhone unlocking and infecting. Not gonna happen no more, no more. I like it. (Drive-by iPhone lock ups? We shall see).
Nevertheless, I expect the future holds further iPhone hacks.

....Android

"...Next are the owners of all the more recent devices. The good news there is that due to geohot’s limera1n exploit, all recent devices can be jailbroken (this will be true until Apple released new hardware that fixes geohot’s limerain exploit in the bootrom)."
Hooraayyy! Apple's incompetence saves us once again!

I WOULD LIKE TO KNOW IF I CAN BLOCK MY IPHONE4 IN CASE OF THEFT AND IF THERE IS A WAY TO LOCATE IT(E.G. VIA GPS)

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