Use an official MFi-certified USB cable. Avoid aftermarket extenders.
This error typically indicates that the connection between your device and the computer was interrupted during the verification stage, or that the software environment (drivers/itunes) is conflicting with 3uTools. 3utools error unable to restore idevice75 link
3uTools has a built-in utility to fix driver issues that cause Error 75. Open 3uTools. Go to the tab. Click on iTunes Utility . Use an official MFi-certified USB cable
: In some cases, it may point to a "solder bridge" issue or low-voltage communication lines on the motherboard, requiring professional microsoldering repair. requiring professional microsoldering repair.