Has your iPhone died?
Want to restore but not upgrade?
Since you have an iPhone 3g or earlier you can restore your phone to an earlier version. This method will notnwork with a 3rd generation iPod Touch or iPhone 3gs as apple must digitally verify all iPhone restores. They as of this writing are not verifying any firmware but 3.1.3 on these two newest iDevices.

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If your phone is in the "connect to iTunes" screen then it likely isnt actually in DFU mode.
DFU mode has to be entered by a user. More on that in a minute.

1. The first thing you need to do is download the appropriate firmware for your device.
You can get a list of firmware downloads from:

The file you want is:
3.1.2 (3G): iPhone1,2_3.1.2_7D11_Restore.ipsw
(or earlier)

Download that file. They are large so be patient. Also take note of where it is saved as you need it later on.

Now you are ready to put the phone into restore mode if it isn't already:

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.

At this point you will see a message in itunes telling you that an iPhone in recovery mode and that it needs to be restored.
Click ok to dismiss this dialog box.

Next on the iTunes screen hold SHIFT and click the restore button.
Instead of downloading the newest firmware it opens a file dialog box.

Navigate to the file you just downloaded and select it.
The rest of the process is automated and will take maybe between 15-20 minutes.

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