The loader is usually extracted from the official Apple firmware (.ipsw). If you are trying to restore to a version of iOS that is no longer signed, or if you downloaded the (Global) firmware instead of the iPhone9,3 (GSM) firmware, the tool will fail.
When a restoration tool attempts to put your phone into a state where it can accept new firmware, it needs a "loader" file tailored exactly to this model and board. If the tool can't find this file in its own database or within the IPSW (firmware file) you provided, it throws this error. Common Causes and Fixes 1. Outdated Restoration Tools
Many restoration tools require you to manually point to a BuildManifest.plist . If this file doesn't match the firmware or the device, the loader won't be identified.
If you are stuck and need to get your iPhone 7 back to a working state:
Are you currently trying to to a specific iOS version, or are you just trying to unbrick the device?
Hard reset your iPhone 7 (Volume Down + Power) while connected to a computer until the screen stays black.
Try a standard "Restore" using the official Apple methods. This will update you to the latest iOS version but will almost always clear "loader not found" errors.
This is the internal model identifier for the iPhone 7 (specifically the GSM model).
If you are attempting to "downgrade" your iPhone 7, the error might occur because the current "Signed" SEP (Secure Enclave Processor) firmware is incompatible with the version you are trying to install.
