When a SID has been used as the unique identifier for a user or group, it cannot ever be used again to identify another user or group. The system uses the SID in the access token to identify the user in all subsequent interactions with Windows security. Each time a user logs on, the system retrieves the SID for that user from the database and places it in the access token for that user. Each account has a unique SID that is issued by an authority, such as an Active Directory domain controller, and stored in a security database.

If the SID cannot be resolved, you will see the source data in the event.Ī security identifier (SID) is a unique value of variable length used to identify a trustee (security principal). Event Viewer automatically tries to resolve SIDs and show the account name. Security ID : SID of account that reported information about logon failure. Minimum OS Version: Windows Server 2008, Windows Vista. For recommendations, see Security Monitoring Recommendations for this event.

Windows 10 security tab