My iPhone refuses to boot and when I followed an instruction posted here to connect it to iTunes and holding down the power and home button and letting go after 6 seconds, it told me to restore but when I did this, it returned an error 3194

Hi..
You would have to restore the iPhone by connecting it to iTunes..
if you are not able to do so follow below given instructions..

1. Turn the iPhone off
2. Press and hold the home button
3. While holding the home button connect the iPhone to the computers USB port
4. Once you get a pop up stating ... iTunes has detected an iPhone in recovery mode you can let go the home button.
5. Click restore on iTunes and follow on screen instructions.


Regards,
Kamran

put your iphone on the a/c charger and press and hold the power and home buttons until you see the apple logo come up. it will then
boot up again. if it stops at the logo then you will need to restore the software,
use DFU mode to restore,
How to enter iPhone DFU mode

• Connect the iPhone to your computer and launch iTunes
• Turn the iPhone off (hold down the power button at the top of the iPhone)
• Hold down the sleep/power button and home button together for exactly 10 seconds, then release the power button
• Continue to hold down the Home button until a message appears in iTunes telling you an iPhone in recover mode has been detected

proceed with this steps and fix it. God bless you
If the device is powered off, plug one end of your USB cable into the iPhone and leave the other end disconnected. Press down on the Home button, and keep holding it down while you plug the USB cable into your computer. After 5-10 seconds, you should see a "Please Connect to iTunes" image on the iPhone 4S, and iTunes should prompt you to restore the software; follow the prompts and the instructions given above.
If the device is powered on, hold down both the power and home buttons until the device reboots and displays the "Connect to iTunes" image (generally, 5-15 seconds).

Corrupted software

It isn't often that Apple gives specific directions about how to fix your problem! Restoring the iPhone 4S will erase everything on it, so make sure everything on the iPhone 4S is stored elsewhere prior to restoring. To restore, connect your iPhone 4S to a computer with iTunes installed. Click "Restore" on the iPhone 4S summary page (click on your iPhone icon on the left menu to find this page). Follow the directions to restore. If your iPhone 4S displays the text "Please wait. Very Low Battery," leave it plugged in. This charges the iPhone 4S enough to be able to restore. If the iPhone 4S hangs on this screen for long periods of time, you may need a new battery.

Force restore mode

If your iPhone 4S is hanging with an Apple logo, or exhibiting some other software problem that prevents iTunes from recognizing it, you can force it into recovery/restore mode and then use iTunes to restore the software.
If the device is powered off, plug one end of your USB cable into the iPhone 4S and leave the other end disconnected. Press down on the Home button, and keep holding it down while you plug the USB cable into your computer. After 5-10 seconds, you should see a "Please Connect to iTunes" image on the iPhone 4S, and iTunes should prompt you to restore the software; follow the prompts and the instructions given above.
If the device is powered on, hold down both the power and home buttons until the device reboots and displays the "Connect to iTunes" image (generally, 5-15 seconds).
God bless you

I suggest you try connecting it to iTunes when you start it up, if same thing, You can put your iPhone into DFU mode then connect it to iTunes and from there see if you can restore your iPhone or fix the repeat boot issue.
By any chance is this Jailbroken as a failed upgrade via iTunes with a JB iDevice can cause this (previous experience).
Step 1. Turn off your iPhone. Step 2. Hold down the power and home button. Step 3. When you see the Apple logo, release the power button but continue holding the home button down. Step 4. Open iTunes and wait for it to tell you that its in restore mode.
Alternative Method: Step 1. Connect iphone to USB then listen to the sound when it connect and disconnect. Step 2. Hold the home and power buttons until hear the disconnect sound then release power button. Step 3. Wait until you hear another sound then release home button.

Hi

Have you tried holding the power button and the home button on the front for around 10secs?

Try this, the Apple logo should appear and get the phone to boot up.

If that doesnt work, boot up your computer and make sure you have the most recent version of itunes on it and then hold down the home button on the front of the phone while plugging into your computer and keep holding down the home button until you get a message on itunes saying an iphone has been detected in recovery mode. Then release the button and restore your iphone as a new iphone

**** Because your phone wont power on and it has been restarted this way you need to restore as a new iphone to get it to work again meaning you will loose any info on the phone ****

Make sure you update your phones software its most likely a factor to your phone shutting itself down.

Ive put the details below on how to restore your iphone, while restoring it will automatically update it for you - (after holding the home button and receiving the message on itunes follow the restore info)

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1. Select the Restore option.
2. When prompted to back up your settings before restoring, select the Back Up option (as seen in the image below). If you have just backed up the device, it is not necessary to create another.
   
3. Select the Restore option when iTunes prompts you (as long as you've backed up your device, you should not have to worry about restoring your phone).
   
4. Once the restore process has completed, the device restarts and displays the Apple logo while starting up:
   
   iPhone only: For the iPhone only, after a restore, the iPhone displays the "Connect to iTunes" screen. Keep your device connected until the "Connect to iTunes" screen goes away or you see "iPhone is activated." If iTunes does not have an Internet connection, you cannot complete this step.
   
5. The final step is to restore your device from a previous backup. Once your device is restored and-in the case of the iPhone-in the process of activating, you should be able to see the following in iTunes:
   

Select set up as a new iPhone :0)

To resolve this issue, you will need to restore your iPhone to factory settings This means any data (music, movies, contacts, etc.) will be erased and the iPhone brought back to it's factory settings (like the day you got it).
To do this, follow the steps below:
1. Make sure your iPhone is disconnected and powered off. If it's not already, hold down the power button until the "Slide to Power Off" message is displayed and swipe to turn off.
2. Connect the USB end of the data cable to your computer, do not connect the other end just yet.
3. Connect the other end of the data cable to the iPhone and immediately press down & hold the "Home" button.
4. Continue to hold down "Home" button , until the iTunes logo appears and the USB connection is displayed on the iPhone's screen.
5. Open iTunes (if it hasn't opened automatically) and a message stating that it has found an iPhone that is in recovery mode. (If you don't get this message and the iPhone just boots like normal, then the timing between connecting the iPhone and holding the home button wasn't fast enough. Try again from step #1).
6. Click the "Restore" button and iTunes will automatically download and install the latest iOS version for your iPhone.
The process should take about 20-45 mins, depending on your internet connection. Once complete, the iPhone will reboot and will be restored to factory settings.
Since iTunes requires that all data be synced through there, if you have made any backups to your iPhone, you'll be able to re-sync your information back to your iPhone at this time.

If this will not boot at all try plugging it to your computer and see if iTunes can do a restore.

If this fails try putting your iPhone device to recovery mode by doing the following steps:

1. Plug your USB cable into your computer.
   
2. Turn your iPhone off by holding the power button down until you see “slide to power off”. Do as instructed.
   
3. Now press and hold the Home button while reconnecting the USB cable to your iPhone. After iPhone is connected it should power on the device.
   
4. Continue holding the Home button, you will see the Apple logo appear and then finally a “Connect to iTunes” will be displayed, now is the time to release the Home button. You will then see the following image:
   

Is this an Iphone MSDC usually point you to the SD card ???.

If it is the Iphone then i suggest doiing a recovery on it

1. Make sure you have the latest version of iTunes (8.0.2)
   
2. Plug your USB cable into your computer.
   
3. Turn your iPhone off by holding the power button down until you see “slide to power off”. Do as instructed.
   
4. Now press and hold the Home button while reconnecting the USB cable to your iPhone. After iPhone is connected it should power on the device.
   
5. Continue holding the Home button, you will see the Apple logo appear and then finally a “Connect to iTunes” will be displayed, now is the time to release the Home button
   

then follow the onscreen instruction in Itunes

You need to try to do a hard reset, then a restore. Follow instructions below:
1. Hold down home and power button together until screen turns completely black.
2. Open up iTunes on your computer
3. While holding down the home button, plug your iPhone into your computer and continue holding down home button until iTunes recognizes the iPhone
4. Should see dialog box from iTunes saying, "iTunes has detected an iPhone in Recovery Mode, you must restore this device"
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