When you initiate the within HScan 1.2, the tool performs a sequence of operations against target IP ranges or individual hosts on port 25 (the default SMTP port).
Modern providers like Microsoft Outlook and Google have deprecated Basic Authentication in favor of TLS 1.2 and OAuth2 , making older unauthenticated scanners largely ineffective for modern enterprise servers. Legitimate Alternatives for SMTP Scanning Smtp Scanner Hscan 1.2 Download