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Save the digital signature (ECID)

All iPhone 3G, 3GS, 4 and iPad owners, who in the future want to have a jailbreaked phone despite the firmware version, need to keep the ECID certificate.

Attention! The digital signature is saved only for the currently relevant firmware version. This means that after the release of iOS 4.1, you can not save the signature from 4.0.1, even despite the fact that you have it installed.

Therefore, press the button as soon as possible!

The easiest way is to save the SHSH files on Saurik's servers in Cydia. So, run Cydia and click on Make my life easier, thanks!

After that, your device will wait for the request to be processed and you will see the following inscription on top - This device has a pending TSS request , but as soon as the signature is saved the message changes to This device has SHSHs on iPhone for iPhone OS: 4.0 , where the numeric value corresponds to the version firmware on which you are guaranteed to be able to roll back.

Everything, the signature is saved, now in the future this phone can be jailbreaked easily!

You can also save the signature on the computer, this is the most reliable option, but I advise you to start with Cydia.
To do this, download the program TinyUmbrella 4.01.03
TinyUmbrella 4.01.03 [ TinyUmbrella 1/4/03 ] [ TinyUmbrella 1/4/03 ] [ TinyUmbrella 1/4/03 ]

After starting the program, connect the device to the computer and click on the button "Save my SHSH" and after a while your signature will be saved on your PC in the folder C: \ Users \ Username_ \ .shsh \