How to downgrade iPhone software to enable tethering via developer profile

[rivkid]

Hi. I have an iPhone 3GS running 3.1.3. I want to install a developer profile to enable tethering (AT&T) without jailbreaking. How can I do this? I tried installing the developer profile (while running 3.1.3) and it installed, but it didn't work. Is there a hardware restriction as well?

 

[Applejuiced]

You wont be able to downgrade your firmware unless you have your SHSH's saved either locally or on Cydia.
And since you were not JB before you probably dont have either so I dont think its going to happen.

 

[rivkid]

You wont be able to downgrade your firmware unless you have your SHSH's saved either locally or on Cydia.
And since you were not JB before you probably dont have either so I dont think its going to happen.

But what about the thing where you can press Shift and restore, and use a downloaded version of 3.1.2?

 

[Makaveli6103]

But what about the thing where you can press Shift and restore, and use a downloaded version of 3.1.2?

That wont work if you dont have your SHSH on file with cydia. When you press Shift and restore you can click on a 3.1.2 software but ituens talks to apple HQ and will not authorize it. when you have your SHSH on file you trick itunes into allowing 3.1.2 by itunes talking to another server.

 

[rivkid]

That wont work if you dont have your SHSH on file with cydia. When you press Shift and restore you can click on a 3.1.2 software but ituens talks to apple HQ and will not authorize it. when you have your SHSH on file you trick itunes into allowing 3.1.2 by itunes talking to another server.

Ok, thanks. I never jailbreaked, so I don't have any cydia stuff. is there any way i can still unlock tethering from 3.1.3 on a 3GS without jailbreaking?

 

[Applejuiced]

But what about the thing where you can press Shift and restore, and use a downloaded version of 3.1.2?

Give it a try and see what happens.
You will get this: "iPhone cannot be restored. This device isnt eligble for the requested build"

 

[Applejuiced]

Ok, thanks. I never jailbreaked, so I don't have any cydia stuff. is there any way i can still unlock tethering from 3.1.3 on a 3GS without jailbreaking?

No

 

[The General]

But what about the thing where you can press Shift and restore, and use a downloaded version of 3.1.2?

hey, yeah, you're right. all of these developers and hackers just hadn't thought of that yet.

no. you cant do it.