Value: 4000
The WebEventCodes.AuditCodeBase value represents the offset for the major event code range associated with the System.Web.Management.WebAuthenticationSuccessAuditEvent, System.Web.Management.WebSuccessAuditEvent, System.Web.Management.WebAuthenticationFailureAuditEvent, System.Web.Management.WebFailureAuditEvent, and System.Web.Management.WebViewStateFailureAuditEvent types.
All audit codes are assigned values greater than WebEventCodes.AuditCodeBase.