SignetKeys

macOS code signing & notarization errors

A plain-English reference for the exact errors developers hit when signing and notarizing macOS apps, installers, and audio plugins (VST3/AU/AAX). Each page explains what the message means, why it happens, and how to fix it — with the commands to confirm the fix worked.

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Signing errors

Notarization errors

Why these keep happening

Almost every failure above comes from hand-rolling the signing steps in CI: a flag forgotten, a file touched after signing, a step run in the wrong order, or a build that was signed but never notarized. The SignetKeys pipeline runs the whole inside-out walk — sign, timestamp, harden, notarize, staple, verify — as one correct sequence, with your Developer ID held in hardware custody and zero secrets in your CI. See how it works →