solution
Here are a few steps that can help solve the problem
Restart the computer
Maybe with just restart your Mac or Windows PC can successfully restore your iPhone.
Try a different USB port
Connect the iPhone to a different USB port on your Mac or Windows PC. It is preferable to use the USB 2.0 ports on the computer. After that, try restoring your iPhone in iTunes.
Restarting the Apple Mobile Device Service (Windows only)
Restarting the Apple Mobile Device Service on Windows XP or Windows Vista, you may be able to successfully restore your iPhone. See steps below depending on your version of Windows.
Windows XP
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Close iTunes and disconnect the iPhone.
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Select Start> Control Panel.
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Once in the Control Panel, open Administrative Tools.
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Open Services.
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Select Apple Mobile Device and click Stop the service as shown below:
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When the service has stopped, click Start the service.
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When you have returned to start the Apple Mobile Device Service, open iTunes and connect the iPhone.
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Select iPhone in the Source list, click the Summary tab and click Restore.
Windows Vista
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Close iTunes and disconnect the iPhone.
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Click the Start button in Windows
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In the Start Search field type "Services".
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In the Programs of the search results section, click on "Services".
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Select Apple Mobile Device and click Stop the service as shown below:
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When the service has stopped, click Start the service.
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When you have returned to start the Apple Mobile Device Service, open iTunes and connect the iPhone.
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Select iPhone in the Source list, click the Summary tab and click Restore.