First when I tried to downgrade from iOS 4.0.2 to 4.0.1, I kept getting Error 3194. For the second time I tried to downgrade, I got the Error 3014. Now, I have successfully downgraded my iPhone 3GS in my Windows 7. This article is a guide for people who wanna downgrade from iOS 4.0.2 to 4.0.1 in Windows 7. I am not sure if the following steps will work in other version of Computer OS or iOS. But you can give a try on it.
STEP 1: Right click on your Notepad, and click “Run as Administrator”.
STEP 2: Navigate to C:\Windows\System32\drivers\etc\ and open “host” file. If you see “127.0.0.1 gs.apple.com” or “# 127.0.0.1 gs.apple.com”, please delete it. And, paste “126.96.36.199 gs.apple.com” into the last line without putting “#”. Then, save it.
STEP 3: You must have SHSH blobs saved on Saurik’s server in Cydia, now let us download it to our computer.
> Connect your iPhone 3GS to your computer, start TinyUmbrella and Tick the Advanced Options.
> Select “iPhone3GS 4.0.1 (8A306)” for Device/Version and “Cydia” for Request From.
> Press the button “Save My SHSH”. Leave or minimize the TinyUmbrella.
STEP 4: Now, open your latest version of iTunes. The following step is to put your iPhone 3GS into DFU mode. Hold Home button and Sleep/Wake button simultanously and start counting to 10 (seconds). Then, leave Sleep/Wake button while you are still holding the Home button, for another 10 seconds thereabout until your iTunes detects the recovery mode. Press OK. At this point, your iPhone will show black screen instead of Apple logo screen. If you get Apple logo screen, kindly try again the DFU mode steps.
STEP 5: Run the TinyUmbrella again. Then, click on the “Display SHSH” button to ensure that your SHSH blobs has been saved. Click on the “Start TSS Server” button and let it keep running.
STEP 6: Hold down SHIFT key on your keyboard and mouseover to “Restore” in iTunes and click it. Choose the “iPhone2,1_4.0.1_8A306_Restore.ipsw” that you have downloaded earlier. Let the process begin and it will be completed in a moment. After completion, you may restore from any backups or start your iPhone as a new phone.
Many authors mentioned that iTunes will show Error 1011, 1013 or 1015. But, I didn’t get any of them. However, according to them, these errors do nothing as your phone will still be downgraded successfully. I do hope this guide helps people who need it out there. Feel free to leave a comment here and you will get quick respond from me. Thanks.