Email Security & Domain Infrastructure

Email Deliverability and Authentication Troubleshooting

A focused diagnostic engagement for legitimate email that is rejected, deferred, routed incorrectly, or classified as spam.

Describe the delivery problem
01

Start with the message path

Review complete headers, authentication results, Return-Path and DKIM identities, sending IPs, relay and connector behavior, and the response from external receiving systems.

02

Investigate the likely cause

The cause may be SPF, DKIM, DMARC alignment, DNS, routing, reputation, recipient policy, or a third-party platform configuration. A single DNS change is rarely enough without understanding the path.

03

Work across the platforms involved

Troubleshooting may involve Microsoft 365, Google Workspace, Salesforce, marketing and helpdesk platforms, transactional senders, relays, registrars, and DNS providers.

04

Define the next step

The result is a written diagnosis and a recommended correction path. A focused investigation can remain separate from a larger DMARC implementation if that is the appropriate scope.

PROCESS

How the engagement works

Start with a representative failed or misclassified message. Trace its path through authentication, DNS, routing and the platforms involved, then document the supported correction and any next decision.

INPUTS

Typical inputs

Complete message headers, recipient or sender context, relevant bounce or deferral responses, DNS and authentication records, and details about the Microsoft 365, Google Workspace or third-party path involved.

DELIVER

What you receive

A written diagnosis, supporting header or routing evidence, the recommended correction, and confirmation testing where implementation is included.

BOUND

Scope boundary

This is defined email-security and domain-infrastructure work—not a substitute for general managed IT, mailbox administration, endpoint management, or an always-on security operations service.

FIT

Common situations

Messages work for some recipients but not others, a vendor integration introduced failures, legitimate mail began landing in spam, or a message authenticates successfully but does not align with the visible From domain.

Start with the domain.

Share the domain involved, the problem you are seeing, and any known email platforms or senders.

Describe the delivery problem