SMTP Email Error 500 5.7.1 – Causes, Fixes, and Prevention Strategies
SMTP Email Error 500 5.7.1 occurs when an email server rejects a message due to authentication failures, blacklisted IPs, or policy violations. Common causes include incorrect login credentials, relay access restrictions, or misconfigured SPF, DKIM, or DMARC records. To fix the issue, verify credentials, update DNS settings, and reduce spam-like content. Monitoring sending limits and…