Error 3194 means iTunes can't reach Apple's signature verification server. Without this verification, the restore or update won't proceed.
Why this happens
The most common cause is a modified hosts file. Jailbreak tools redirect Apple's server address. If that redirect remains, iTunes can't connect. Other causes include outdated iTunes, firewall blocking, or trying to install an unsigned iOS version.
How to fix it
Check your hosts file
Delete any line containing gs.apple.com.
Mac: sudo nano /etc/hosts
Windows: Notepad (Admin) → C:\Windows\System32\drivers\etc\hosts
Update iTunes
Older versions can't communicate with current Apple servers.
Only restore to the latest iOS
Apple stops signing older versions. You can only restore to what's currently signed.
Disable security software
Antivirus/firewall can block iTunes. Temporarily disable them and retry.
Error 3194 is almost always a software/network problem — not hardware.
If none of the above works, the issue is most likely physical hardware damage — a failing chip, corroded connector, or broken internal component. If you've tried everything above and the error keeps coming back, the problem is most likely physical — something broken inside the device that software can't fix. That's when it needs professional hands-on inspection.