Use the iTunes Utility found in the 3uTools "Toolbox" to automatically fix or reinstall Apple Mobile Device drivers.
Sometimes the device is stuck in a limbo state (e.g., Recovery Mode loop but with a corrupted bootloader). In this case, the device rejects incoming ramdisk data. error unable to load restore ramdisk 3utools
Wed May 9 23:17:04 2013 [INFO] Ramdisk signature verified. Wed May 9 23:17:04 2013 [INFO] Loading restore devicetree... Wed May 9 23:17:05 2013 [WARN] Non-standard entropy detected in /dev/random. Wed May 9 23:17:06 2013 [ERR] Restore ramdisk load failed: permission denied (system@ap.nonvolatile:0x7F3A) Use the iTunes Utility found in the 3uTools
The error in 3uTools typically occurs during the flashing or restoration process, often stalling around 19%–21%. This error indicates a communication failure between the software and the device's hardware, often caused by driver glitches, faulty physical connections, or deteriorating internal components like the NAND memory chip . Common Causes Wed May 9 23:17:04 2013 [INFO] Ramdisk signature verified