Hello OmPRakash69,
Thank you for your question!
It sounds like you are trying to update the phone to the latest version of iOS but are getting an errorr message saying the phone is not eligible for the requested build. Try out the troubleshooting in this article named:
Error 3194 or "This device isn't eligible for the requested build"
http://support.apple.com/kb/ts4451
These steps will get you started, and there are additional troubleshooting steps if needed in the article:
Important: If you see one of these messages and need help updating or restoring your iOS device, Install the latest version of iTunes and try to update or restore again. After that, follow these steps if you need more help.
Check your "hosts" file
After you've updated iTunes to the latest version, you can check the hosts file to be sure your computer can contact the update server. Use the numbered steps below if you’re on a Mac.
If you’re using a Windows computer, follow steps in this Microsoft support article, noting that resetting the hosts file will affect software services that rely on hosts file redirects. If you're using Windows on a business computer, consult your IT department to be sure applications will still work correctly after resetting the hosts file.
- In the Finder, choose Applications > Utilities.
- Open Terminal.
- Enter this command and then press Return:
sudo nano /private/etc/hosts
- Enter the password you use to sign in to your computer and press Return. You won't see text appear in the Terminal window when you enter the password. Make sure you use a nonblank administrator password.
- Terminal will display the hosts file. Navigate using the arrow keys and look for an entry containing “gs.apple.com”.
- Add the # symbol and a space ("# ") to the beginning of the gs.apple.com entry.
- Press Control-O to save the file. Then, press Enter when prompted for the filename and Control-X to exit the editor.
- Restart your computer.
- Try to update or restore your iOS device again.
Thank you for using Apple Support Communities.
All the very best,
Sterling