If you don’t have an entry in the host file for “gs.apple.com” and still getting Error 3194, then temporarily disable the firewall or anti-virus software on your computer, as it is quite possible that they’re preventing i Tunes from connecting to Apple servers.
You may also get the “This device isn’t eligible for the requested build” error message if you’re trying to update or downgrade your device with a firmware file that Apple has stopped signing.
In this case, you have to sync separately to find what kind of data you can’t sync.
However, the "i Tunes sync error 54" still can’t be fixed.
Don’t Miss: How to Fix App Store Won’t Download/Update on i Phone This sync error 54 is one common i Tunes problem people may face when updating PC to a new Windows operating system.
In some rare cases, i Tunes seems to also throw the unknown error (3194), if there is a connectivity issue with the update server.
You could try again to see if it goes through successfully.
To give you an example: As of now i OS 8.1.3 is the latest i OS software update.