Complete procedures with a way back.

npm reports UNABLE_TO_GET_ISSUER_CERT_LOCALLY or SELF_SIGNED_CERT_IN_CHAIN when Node.js cannot build a trusted certificate path for the configured registry or an HTTPS-intercepting proxy. This guide restores an explicit trust chain without disabling TLS verification.

Issue identities from a trusted CA, protect private keys, require encrypted accounts, configure hostname verification, rotate certificates, and test downgrade resistance.