Tool guide limitationsGuides explain the intended workflow but cannot cover every device, provider or operating condition.
Interfaces and external services can change. Follow the current on-screen controls, check dates and vendor documentation, and verify important results independently before acting on them.
Important: Do not rely on this result alone for purchasing, configuration, security, safety, compliance, contractual or fault-diagnosis decisions. Results can be incomplete, delayed, misleading or wrong. Verify important findings with the relevant provider, manufacturer documentation and an appropriate independent test or qualified professional.
DNS and email
Email DNS Configuration Preflight guide
Compare proposed email DNS records with the currently published values before a change.
Open Email DNS Configuration PreflightWhat you need
- Domain
- Proposed SPF, DMARC, MTA-STS, TLS-RPT or BIMI values
How to use it
- 1Enter the domain.
- 2Paste only the records you plan to change.
- 3Run preflight.
- 4Review current-versus-proposed differences and cautions.
Understanding the results
- A difference is not automatically an error; it identifies a change requiring review.
Recommended next actions
- Peer-review the change, record rollback values and confirm the authoritative DNS target.
Common problems
- Replacing rather than merging SPF can remove authorised senders.
Privacy and security
- Proposed values are submitted for comparison; never include passwords or private keys.
Worked example
- Scenario
- Moving DMARC from monitoring to quarantine
- Example input
- Current p=none; proposed p=quarantine
- How to read it
- The comparison highlights the enforcement change so reporting and authorised senders can be reviewed first.
Limitations
- The tool does not publish records or know every vendor requirement.
Do not rely on one result for a production, security, safety, purchasing or contractual decision. Verify important findings independently.