Both recovery and DFU modes are often confusing which just adds to the frustration when accidentally put into either of these modes. You don’t have to restore completely in iTunes. That takes up a lot of time (around 20 minutes and if you have data, it may be longer to get it all back up and running). You can give the following combinations a shot and I have tested them both on iPhone 3.0.

DFU Mode :

Steps to recover from DFU mode :

• Connect your iPhone to your computer.
• Hold down the home button and the power button for about 10 seconds.
• If your phone is connected to your computer you’ll hear a beep as when a USB device is disconnected.
• Next just press the power button and your phone will startup as usual.

If you’ve accidentally put your iPhone in DFU mode, the steps mentioned above should do the trick.

If you’re in DFU and mid-way through a failed restore, then you will need a complete iTunes restore to get you out of the DFU mode.

Recovery Mode :

Steps to recover from Recovery mode :