Many systems built with ScriptCase send email through Microsoft 365/Exchange Online using sc_mail_send() against smtp.office365.com:587 with username/password (SMTP AUTH). The issue is that Microsoft is moving SMTP AUTH toward OAuth (Modern Auth) and, according to the updated timeline, by the end of December 2026 basic authentication (username/password) for SMTP AUTH will be disabled by default for existing tenants (and will be unavailable by default for new tenants). Once Basic is blocked, sends via smtp.office365.com may start failing with errors such as: “550 5.7.30 Basic authentication is not supported for Client Submission”.
Direct impact on sc_mail_send:
- The macro is called with parameters like SMTP host, user, password, from, etc., meaning it is designed for SMTP with credentials; it does not expose parameters specific to OAuth/XOAUTH2.
- Therefore, if a tenant blocks Basic for SMTP AUTH, you must change the approach: use SMTP Relay/Direct Send (connector/IP/TLS) or migrate sending to OAuth/Graph (typically requiring external code/library).