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View Full Version : How to downgrade iPhone iOS 4 to OS 3.1.3


P90PTS
2nd August 2010, 22:25
Have you currently got an iPhone 3G or 3GS and upgraded to iOS4.0 and wish you hadn't as it's silly slow now?

Read on...

Roll back your iPhone 3G or 3GS to OS 3.1.3


Step 1
Before you do anything, sync your iPhone with iTunes and ensure anything you want to keep - including contacts and photos - is on your computer. If you've disabled syncing of contacts, photos and so on it might be an idea to enable them again and do another sync.

I can't stress this enough: the downgrade will wipe your iPhone, and once you're back on OS 3.1.3 you can't restore data from backups made in iOS 4.0 or 4.0.1. That means if something hasn't been copied from your iPhone to your computer and you've added it since upgrading to 4.0 or 4.0.1, you'll lose it permanently.

http://mos.futurenet.com/techradar/classifications/Mobile%20Phones/iPhone/iOs4-downgrade/step11-420-100.jpg

Step 2
Now, we need to find iPhone OS 3.1.3. This should be on your computer: on a Mac, go to your hard disk and open up Macintosh HD > Users > Yourname > Library > iTunes > iPhone Software Updates; on a PC, head for C:\Documents and Setting\Yourname\Application Data\Apple Computer\iTunes\iPhone Software Updates. The one we're looking for is iPhone1,2_3.1.3_7E18_Restore.ipsw. If it isn't there, download it (http://redirectingat.com/?id=92X363&xs=1&url=http%3A%2F%2Fappldnld.apple.com.edgesuite.net% 2Fcontent.info.apple.com%2FiPhone%2F061-7468.20100202.pbnrt%2FiPhone1%2C2_3.1.3_7E18_Resto re.ipsw&sref=http%3A%2F%2Fwww.techradar.com%2Fnews%2Fphone-and-communications%2Fmobile-phones%2Fhow-to-downgrade-iphone-ios-4-to-os-3-1-3-704705).
Please note this file is for a 3G, not a 3GS: if you're downgrading one of them for whatever reason, the .ipsw file you need starts iPhone2,1

http://mos.futurenet.com/techradar/classifications/Mobile%20Phones/iPhone/iOs4-downgrade/step2-420-100.jpg

Step 3
Time for another download: RecBoot (http://redirectingat.com/?id=92X363&xs=1&url=http%3A%2F%2Fwww.sebby.net%2F443-recboot-final-release%2F&sref=http%3A%2F%2Fwww.techradar.com%2Fnews%2Fphone-and-communications%2Fmobile-phones%2Fhow-to-downgrade-iphone-ios-4-to-os-3-1-3-704705). On Windows, you'll also need to make sure you've got .NET 4.0 installed, and if you're running Vista or Windows 7 you'll need to run it in Compatibility Mode. Full instructions are here (http://redirectingat.com/?id=92X363&xs=1&url=http%3A%2F%2Fjoshuabailey1997.wordpress.com%2F 2010%2F05%2F16%2Frecboot-easily-boot-your-device-intoout-of-recovery-mode-with-one-click%2F&sref=http%3A%2F%2Fwww.techradar.com%2Fnews%2Fphone-and-communications%2Fmobile-phones%2Fhow-to-downgrade-iphone-ios-4-to-os-3-1-3-704705).
Now, put your iPhone into recovery mode. To do that, connect your iPhone to your computer and switch it off. When it's completely off, press and hold the power button and the Home button for ten seconds and then let go of the power button. Keep pressing Home until iTunes says that it "has detected an iPhone in recovery mode".

http://mos.futurenet.com/techradar/classifications/Mobile%20Phones/iPhone/iOs4-downgrade/step3-420-100.jpg

Step 4
If iTunes hasn't done it already, select your iPhone in the left hand iTunes panel so the Restore button is visible. Don't just click it, though: Alt/Option-Click it if you're on a Mac and Shift-Click it if you're on a PC. This enables you to select the file to restore from, which is the .ipsw one we looked for earlier, so locate that, select it and click on Choose.


http://mos.futurenet.com/techradar/classifications/Mobile%20Phones/iPhone/iOs4-downgrade/step4-420-100.jpg

Step 5
iTunes will now give you a factory-fresh iPhone 3G running OS 3.1.3. The process takes ten minutes or so, and when it's finished iTunes will probably tell you that the iPhone couldn't be restored because of an unknown error. Don't worry about this: that's why we downloaded RecBoot. On a Mac, run the RecBoot Exit Only application; on PC, launch RecBoot. Now, select Exit Recovery Mode

http://mos.futurenet.com/techradar/classifications/Mobile%20Phones/iPhone/iOs4-downgrade/step5-420-100.jpg

Step 6
Your iPhone should now restart, and after a moment iTunes will ask whether you want to set it up as a new iPhone or restore from a backup. Now that you've downgraded you can't restore from iOS 4.0 or 4.0.1 backups, so you'll have to choose a pre-iOS 4 backup (if you have one). The restore process takes about ten minutes

http://mos.futurenet.com/techradar/classifications/Mobile%20Phones/iPhone/iOs4-downgrade/step6-420-100.jpg

Step 7
Your iPhone should restart again, but it's not ready to use yet: now, you need to sync it. That means copying across all your music, all your movies, all your apps… this would be a good time to make dinner, start a family, make a volcano from mashed potato or write the Great American Novel. Depending on how much stuff there is to sync, syncing your newly restored 3G can take hours. Trust us. It's worth it.

http://mos.futurenet.com/techradar/classifications/Mobile%20Phones/iPhone/iOs4-downgrade/step7-420-100.jpg

Paul.


Thanks to Gary Marshall at Techradar.com