How to Fix the error This device isn't eligible for the requested build when restoring iPhone in iTunes

 Sometimes when you restore to the latest version of iPhone firmware, it iTunes may prompt with the error "This device isn't eligible for the requested build" and the restore fails afterward. You may try the following steps in order to get past the error

For PC:

1. Open the hosts file located in the folder below:

Windows 95 - C:windows
Windows 98 - C:\windows
Windows Me - C:\windows
Windows 2000 - C:windows\system32\drivers\etc
Windows XP - C:\windows\system32\drivers\etc
Windows NT - C:\winnt\system32\drivers\etc
Windows Vista - C:\windows\system32\drivers\etc 

2. Remove any line that has gs.apple.com in it

3. Save and close

4. Open the command console

5. Type ipconfig/flushdns

6. Restart iTunes

For Mac:

1. Type the terminal in spotlight and start the Terminal app

2. Type sudo vi /private/etc/hosts in Terminal

3. Remove any line that has gs.apple.com in it

4. Save and close by typing :wq! 

5. Type dscacheutil -flushcache

6. Restart iTunes

Now try restore again and it should work for you error free.