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As several iPhone four users move to the iOS four.2.1 version they will not prisonbreak their iPhone or unlock their iPhone. Some users is also able to unlock their iPhone four even if several tricks will prisonbreak them. therefore this tune for them. you'll be able to simply prisonbreak and unlock your iPhone if you have got the straightforward steps of tune-up. This tune is merely for iPhone four users. you'll be able to simply get another version of your iPhone (3G, 3GS ...) by Jebel Bracke from the ordinal episode.

Let United States of America see the way to update your iPhone four's BaseBand while not change the iOS 4.2.1 version -

1. transfer the TinyUmbrella package from the subsequent transfer links in line with your most well-liked software -

For Windows: TinyUmbrella for Windows
For Mac: TinyUmbrella for mackintosh

The on top of version is supported with CDMA, whose supplier Verizon
You also have to be compelled to transfer the frameware version for the iPhone four from the subsequent sites.

iPhone four code four.2.1
It's just for iPhone four.

1. Connect your iPhone to four computers. Then double click on TinyUmbrella package. Unblock if there's a security message.

If TinyUmbrella will with success find your iPhone, then you'll be able to get all the small print of your iPhone four within the General Tab window shown below. like iPhone Model, code version, baseband version

1. If there's a retardant then modification the SHSH of your iPhone beforehand. To do this, click Save SHSH. Once saved, it'll seem on the overall Tab of TinyUmbrella package.

2. when saving SHSH, click "Start syndrome Server". currently the package can try and hook up with that server and WHO can shut the iTunes package at that point. If you get miscalculation message then you'll not be able to proceed more. If you wish to understand the explanation for the error message, move to log tab.

And if everything goes well then you get a massage. The message is "TSS Server running successfully". additionally within the "Start syndrome Server" area then "Stop syndrome Server" can seem. ne'er click on "Stop syndrome Server".
Whenever you see this message, flip it back on iTunes.

1. Whenever iTunes is launched, your iPhone can seem within the list. If iTunes asks you to update your iPhone, please do no. Then click on your iPhone. you'll see associate degree choice with Restore on the positioning. Hold Shift and click on Restore. currently a window can return. this can show you the primary downloadable frameware version (Browse). when browsing the frameware version, click Restore. iTunes can currently begin change your iPhone.

2. you'll be able to get error 1013 from iTunes. As presently because the message is received, shut iTunes. 1013 suggests that "Your baseband has not updated. Press alright to continue." .

If you get a message like 16XX, then get your iPhone in DFU and follow step five once more.
If you are doing not receive any 1013 message, then you wish to grasp that your baseband was updated.

1. currently future step is to jailbreaking your phone. you'll be able to see this
   tune if you wish to jailbreaking your iPhone.

------ Warning ------

If you have got any downside together with your iPhone to follow this tutorial then i will be able to not be accountable.
So do no matter you are doing, at your own risk.
However each step and a focus to that
If you're doing well, there's no downside reaching to be over attainable.