Following a recent password change, a user can log on successfully to an Apple computer but cannot access a web-based service. An error message displays each time the user attempts lo authenticate…

passwd is a Unix command-line utility for changing a local user account password and has no function related to stored web service credentials.

FileVault is Apple's full-disk encryption feature and plays no role in storing or managing web service authentication credentials.

macOS Keychain Access stores saved usernames and passwords for web services, applications, and network resources separately from the local login password. After the user changes their local account password, the Keychain entry for the web-based service still contains the old credential, causing repeated authentication errors. The technician should open Keychain Access, locate the entry for the affected service, and update or delete the stale password.

Gatekeeper controls which applications are permitted to run based on their digital signature and source, and is unrelated to stored web service login credentials.