iPhone 3G downgrading firmware

[momiller]

I have an iPhone 3G which is running slowly. It was suggested to me to downgrade the firmware to 3.1.3. I'm now on 4.2.1. Everywhere I looked to downgrade it the phone has to be jailbroken before I downgrade it. Is there a way to downgrade it without jailbreaking it? If so how?

Thanks in advance.

 

[-aggie-]

You must jailbreak. What's your problem with jailbreaking? You'll never want to go back after you do.

 

[Crystal-RX]

Your phone does not need to be jailbroken in order to be downgrade to 3.1.3, this is wrong. Follow the following steps;

1. Download 3.1.3 IOS for 3G to your PC.
2. Download Tiny umbrella to your PC.
3. Hook up your phone to PC
4. Open Itunes, shift + restore at the same time and select 3.1.3 to restore.
5. At the end, Itunes will give you a 1015 error. Run tiny umbrella and hit "exit recovery"
6. You are done!

 

[momiller]

You must jailbreak. What's your problem with jailbreaking? You'll never want to go back after you do.

No problem with jailbreaking, just don't want to deal with the whole process.

 

[momiller]

Your phone does not need to be jailbroken in order to be downgrade to 3.1.3, this is wrong. Follow the following steps;

1. Download 3.1.3 IOS for 3G to your PC.
2. Download Tiny umbrella to your PC.
3. Hook up your phone to PC
4. Open Itunes, shift + restore at the same time and select 3.1.3 to restore.
5. At the end, Itunes will give you a 1015 error. Run tiny umbrella and hit "exit recovery"
6. You are done!

I did as you said. One problem, I can't restore all my information now. It tell me the software is too old! Is there a solution to this or I have to do everything manually?

 

[Applejuiced]

You have to enter it manually.
Sorry.

 

[momiller]

You have to enter it manually.
Sorry.

Oh well. Sucks to be me.