Image file header may be corrupted.
PreFlight checks for MED-004 issues in memory and provides 1-click remediation during client-side packaging.
EPUBCheck detected Image file header may be corrupted.. Digital reading systems and bookstores require standard conformance to ensure compatibility across all reading apps.
Automated book distributors (Apple Books, Amazon KDP, Kobo, and IngramSpark) run strict EPUBCheck validation on ingest and reject non-compliant files.
Technical Specification: W3C EPUBCheck rule MED-004: Image file header may be corrupted.