Overview

Legitimate business emails may be filtered or rejected, affecting sales, support, invoicing, and client response times.

Symptoms

• Users report inconsistent or failed access to the affected service, device, or application.
• Normal business or home workflows are interrupted, delayed, or no longer reliable.
• The issue may be isolated to one user or may affect multiple systems depending on the root cause.

Cause

Poor sending reputation, missing domain authentication, suspicious content patterns, or shared hosting issues often cause this problem.

Resolution

Verify SPF, DKIM, and DMARC, test messages with clean formatting, inspect sending IP reputation, and review whether the issue affects all recipients or only certain providers.

1. Confirm the exact symptoms and identify who or what is affected.
2. Check for recent changes such as updates, password changes, hardware swaps, DNS changes, or policy adjustments.
3. Test the most likely root cause first and document all findings clearly.
4. Apply the corrective action in the least disruptive way possible and verify the issue is fully resolved.
5. Record the final outcome, any user communication, and any recommended follow-up work.

Prevention

Use authenticated sending, keep mailing practices consistent, and monitor domain reputation over time.

When to Contact Support

If the issue continues after standard troubleshooting, affects multiple users, involves data loss risk, or raises security concerns, it should be escalated to a qualified technician promptly.