Downgrade iPhone 3GS from iOS4 to 3.1.3

In order to downgrade all you need to do is.

1. Find the 3.1.3 firmware update somewhere online and download it.

2. Go to iTunes and while holding shift press the restore button on the iPhone screen.

3. Find the update (in this case downdate)where you saved it on your computer.

4. Install and viola, 3.1.3

Hi. This advice did not work. I found the OS version needed and downloaded it. When holding down the Shift key and clicking the Restore button iTunes, you are not presented with any option to locate the downloaded OS for install. It just marches off to the Apple server and reinstalls OS4. Is there something else in the instructions that was missed.

I really really need to get OS4 off my 3g as it is not useable. Please help.

I think you should hold down the option key when clicking restore. But I am not sure thecapple servers will allow you to downgrade.

make sure your iphone is plugged in, highlight your iphone on the side menu bar and hold shift and press restore on the summary screen.

it should bring you to the explorer where you should be able to browse for your file.

this didnt work for me says that i the phone isnt compatible with 3.1.3

im not sure how to fix this os4 is pretty good but im having an issue where it keeps rebooting

You have to had jailbroken for this to be possible.

so, i want to fully understand this... if you had a jailbroken 3.1.3 phone you can downgrade from os4 back to 3.1.3? and, if you go through the restore process and get back to 3.1.3, what about all phone info like contacts, texts, apps etc...??

Instructions for this are not simple nor suggested...Although it was done with previous iOS version on the 3GS and other models...it took a while for folks to hack their way through the steps to FORCE it to work...on purpose Apple does NOT allow you to revert backwards in iOS version once you have upgraded...can it be done yes...but not without a fair amount of finagling...you should instead try to resolve whatever problem you have with iOS4..

What is wrong??

I need to do this too. I upgraded my girlfriends 3GS and it keeps rebooting in the middle of a call. The camera app has been acting oddly too. Sometimes it takes photos and they disappear instead of saving in the photos app.

The phone rebooting constantly is killer for me though, it's not acceptable. You SHOULD be able to downgrade from buggy (for me) software.

By the way, unlike mine, my girlfriend's phone has never been jailbroken.

ShadyMac,

I am DESPERATE to downgrade back to 3.1.3 as because since I upgraded to 4.0 my phone reboots itself at will whilst I am using the phone. This is incredible annoying and renders my phone unusable. I am not alone in this either, check out http://discussions.apple.com/thread.jspa?threadID=2471090.

I have two options; wait for Apple to fix this... or downgrade to 3.1.3 as I effectively have no phone at the moment.

Any help gratefully received. Kind regards all....

See the link below:

http://lifehacker.com/5572003/how-to-downgrade-your-iphone-3g[s]-from-ios-4-to-ios-313

I.M. Shaman wrote:
See the link below:

http://lifehacker.com/5572003/how-to-downgrade-your-iphone-3g[s]-from-ios-4-to-ios-313

Thanks, but as that page says, it won't work for the 3GS, which is what I have. They do point you to a "forum" dedicated to downgrading the 3GS, but I imagine I'll need to poke around in that forum to find a solution - if there is one. Haven't looked at the forum, yet. But thanks, anyway.

I am DESPERATE to downgrade back to 3.1.3 as because since I upgraded to 4.0 my phone reboots itself at will whilst I am using the phone. This is incredible annoying and renders my phone unusable. I am not alone in this either, check out http://discussions.apple.com/thread.jspa?threadID=2471090.

No. You are DESPERATE to get you phone working again. Downgrades are not supported by Apple, and usually involve jailbreaking, which will void any warrantee.

I have two options; wait for Apple to fix this... or downgrade to 3.1.3 as I effectively have no phone at the moment.

Option 3: Get the phone fixed. Most 3GS' are still under warrantee.

So how do we fix the random reboots? (3gs) Do we wait for a patch? Apple doesn't seem to be acknowledging any problems. Matter of fact, re reception issues on the iphone 4 their fix is to hold the phone differently! There has to be a way to downgrade to a working version. We can't just sit and wait three months for the chance of a fix from apple.......