iTunes will detect a problem with the device and offer two choices: Update or Restore .
Disconnect your iPhone and completely close (ensure it is closed in your Windows system tray).
If the phone is stuck in regular recovery mode (cable logo), try booting it into (black screen) before starting the flash in 3uTools.
Always download the firmware directly through the tab in 3uTools, as it automatically fetches the latest signed iOS versions for your exact device model.
before clicking Flash. This bypasses specific battery verification checks that often trigger this error when using a weak battery. Switch to a High-Quality Wired Connection
Windows users must have a clean driver setup.
Desktop users should plug exclusively into the high-voltage USB ports on the back of the PC tower.
Before diving into fixes, it's helpful to understand why this happens. The error is typically caused by one or more of the following fundamental issues:
Standard phone chargers pass data, but a recovery stream requires unbroken power and maximum bandwidth.
If iTunes successfully restores the device, the issue was an internal 3uTools configuration conflict. If iTunes also fails (often throwing an iTunes Error 9, 4005, or 4013), it confirms that the physical USB link is dropping or there is an underlying hardware issue with the device's charging port or logic board.
Before diving into the fixes, it helps to understand why this happens. Usually, it’s triggered by:
Physical connectivity is critical for the “iDevice75 link.”
