iPad / iPhone isn’t eligible for the requested build
If you are trying to update your iPad, iPhone or iPod touch to iOS 5 and get this message “The iPhone “iPhone” could not be restored. This device isn’t eligible for the requested build,” this post is for you.
I have had this issue a couple of times and it was most likely caused from using beta versions of iOS and jailbroken devices. The error message is also sometimes displayed as “error 3194”.
First make sure you have updated to the latest version of iTunes (10.5 in this case) before you update your iDevice to iOS 5.
1. From Finder, click “Go” and then “Go to Folder”
2. Type /etc/ and press return
3. Find the document titled “Hosts” and open it.
4. Find the address “126.96.36.199 gs.apple.com” (or something to that effect) and delete it.
5. Save As to your DESKTOP. (Make sure to uncheck “if no extension is provided, use .txt”)
6. BACK UP the ORIGINAL “Hosts” document to somewhere else on your computer, just in case.
7. Drag and drop the new “Hosts” document you saved to your desktop to the /etc/ folder.
8. Enter your password to verify, and that should work. (If not, replace the new “Hosts” document with the original one.)
All you are trying to do is remove the “188.8.131.52 gs.apple.com” from the Hosts file. Because the file is locked is why we saved it, then replaced it.
If you have any trouble editing the hosts file with the method above, you can also edit the file using Terminal. Here is a tutorial explaining how it is done using Terminal.
Go to: C:\Windows\System32\drivers\etc\ and locate hosts file.
Open and edit the hosts file in Notepad as we did above.
Note: Win 7 and Vista users MUST run Notepad with admin privileges. Right click on Notepad app and select Run as Administrator.
Now you should be able to upgrade your iOS software without getting interrupted by the annoying message.