: This means the diagnostic or flashing software (such as 3uTools, iTunes, or professional repair tools like JCID or iRep) cannot find the necessary "bootloader" or "ramdisk" file needed to initialize the processor for a restore or update. Common Causes Software Incompatibility
If the file is corrupted, delete the existing download and attempt a fresh download through Apple Support or a reputable source. loader for iphone9 3d101ap not found updated