This device isn’t eligible for the requested build iOS 5

Were you trying to install iOS 5 into the iPhone, iPod touch, or iPad but got an error on iTunes saying that “This device isn‚Äôt eligible for the requested build” ?

iTunes will show “This device isn‚Äôt eligible for the requested build” error when iTunes received “No” response from Apple server during verification process while restoring iOS to device.

If you have ever run TinyUmbrella, or manually edit hosts file and didn’t change it back, you probably will have this error because iTunes failed to contact the real Apple TSS server.

How-to make the device eligible for the requested build while restoring iOS 5?

First of all, open command prompt (Windows) or Terminal (Mac) and type ping gs.apple.com command. If you see other response than this:

Reply from 17.112.176.11: bytes=32 time=427ms TTL=49

then you need to change your hosts file.

• Windows Users
• Open Notepad using Administrator’s rights or Administrator’s account on Windows. Start → All Programs → Accessories → right click Notepad → Run as Administrator.
• Click File → Open → browse to C:Windowssystem32driversetc and select hosts file.
• Mac Users
  
  Use text editor and edit /etc/hosts file on Mac (run as root or use sudo)

Find this line:
74.208.105.171 gs.apple.com
Or
74.208.10.249 gs.apple.com

Then

1. Add # sign to the front of it.

   Or, you can simply delete that line.

   Both are IP addresses of Cydia Servers where your SHSH Blobs information will be saved. Adding # sign into that line on your hosts file means that you are making that line as a comment. Or simply delete it from the entries will make your Windows contacting Apple server normally during restore process.

   

2. Save the changes by clicking File → Save or pressing Ctrl + S.

   To verify that you did it correctly, type ping gs.apple.com on command prompt on Windows Accessories (Spotlight → Terminal → ping on Mac) and it must be resolved to 17.112.176.11.

   Example:

   C:>ping gs.apple.com

   Pinging gs.apple.com [17.112.176.11] with 32 bytes of data:
   Reply from 17.112.176.11: bytes=32 time=427ms TTL=49
   Reply from 17.112.176.11: bytes=32 time=429ms TTL=49
   Reply from 17.112.176.11: bytes=32 time=468ms TTL=49
   Reply from 17.112.176.11: bytes=32 time=447ms TTL=49

   Ping statistics for 17.112.176.11:
   Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
   Approximate round trip times in milli-seconds:
   Minimum = 427ms, Maximum = 468ms, Average = 442ms

   C:>

   If you’re getting anything else then it is not good.

   Now, the restore should run smoothly without “This device isn’t eligible for the requested build” error anymore when you are upgrading to iOS 5.