Before I show you how to fix the iTunes error 3194, I want to tell you several things concerning it. First of all, this error is quite common among users lately and it appears when you want to restore the iOS on your iPhone, iPad or iPod Touch. Many people who upgraded their device to the new iOS 6 want to downgrade it to iOS 5 in order to gain their jailbreak status again. Since Apple is not that pleased by this thing, they try to prevent users to downgrade. However, with the help of Cydia, we will be able to do this and avoiding the 3194 error. In fact, the error 3194 appears when iTunes checks Apple for your current SHSH. On the other hand, Cydia can trick Apple and iTunes to use Cydia servers instead of Apple servers.
Step-By-Step guide to fix iTunes error 3194:
Step 1: Close iTunes.
Step 2: Find the host files manually and open them using Notepad. You can find these files in the system files in your computer under the name of Hosts for Mac OS X/Windows. It depends on your operating system. In some cases, you need to run this as administrator. For you select the open as administrator option.
Step 3: in the Notepad document you have opened, type down the 18.104.22.168 gs.apple.com. This will represent the servers when iTunes will check for SHSH.
Step 4: Connect your device to your computer and open iTunes again.
Step 5: Put your device in the DFU mode.
Step 6: Start the restoring of your device as usual by clicking on the Restore button and following those simple steps.
This should be all. Now you should be eligible to upgrade your firmware without encountering those annoying errors. Remember though to remove the line you have typed in the host files in order to give iTunes the possibility to upgrade as normal. I know that it is quite annoying not to be able to upgrade or downgrade as you please. Fortunately, there are many new possibilities through which we are able to perform these processes. With a little bit of patience, we can downgrade or restore our firmware, as we want.