====== Telenegar Mail Check Tool ======

The **Telenegar Mail Check Tool** is a specialized email security diagnostic utility designed to verify **SPF**, **DKIM**, and **DMARC** email authentication records, audit domain security posture, and test whether a domain is a temporary/disposable email provider.

It helps system administrators, email engineers, and security auditors ensure outbound mail deliverability, prevent domain spoofing, and validate mail authentication stack configurations.

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===== Tool Features & Parameters =====

The Mail Check interface provides customized input controls to test email authentication and domain validity:

^ Parameter ^ Description ^ Options / Examples ^
| **Domain Name** | The domain name to audit for email authentication records. | e.g., ''catc.ac.ir'', ''telenegar.ir'' |
| **DKIM SELECTOR** | The prefix selector used by the domain to publish its public DKIM key in DNS (`selector._domainkey.domain.com`). | Default options: ''default'', ''google'', ''s1'', ''mail'', ''k1'' |
| **PROBE** | The remote geographical vantage point or probe location executing the lookup. | ''Falkenstein, Germany — Hetzner Online GmbH'', domestic Iran probes, regional cloud nodes |
| **Auto-detect DKIM selector** | Automatically checks a dictionary of common DKIM selectors if the primary selector is unknown. | Checkbox (tries all common selectors — uses more credits) |
| **Check if domain is disposable** | Cross-references the domain against known databases of disposable, temporary, or burner email providers. | Checkbox (against known disposable email domains) |

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===== How to Perform a Mail Check =====

  # **Enter Domain Name:** Type the domain into the target input field (e.g., ''catc.ac.ir'').
  # **Specify DKIM Selector:** Select or enter a known DKIM selector from the **DKIM SELECTOR** dropdown menu (e.g., ''default'').
  # **Auto-Detect Selector (Optional):** If you do not know the domain's active DKIM selector, check the **Auto-detect DKIM selector** box to scan popular selectors automatically.
  # **Select Probe Location:** Choose a remote vantage point from the **PROBE** dropdown menu (e.g., ''Falkenstein, Germany — Hetzner Online GmbH'') to test DNS resolution from a specific region.
  # **Check Disposable Status (Optional):** Check **Check if domain is disposable** to verify if the domain belongs to a temporary or disposable email service.
  # **Execute Audit:** Click the blue **Check** button to run the verification suite and inspect the results.

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===== Key Use Cases & Diagnostics =====

==== 1. Email Authentication Stack Audit ====
Verify that the core email security protocols are properly published in DNS to prevent spoofing and improve inbox placement:
  * **SPF Verification:** Parses `v=spf1` TXT records, checks authorized IP mechanisms, and detects lookup limit errors (10-lookup max limit).
  * **DKIM Verification:** Fetches the public key record at `[selector]._domainkey.[domain]` and validates record format and key strength.
  * **DMARC Policy Audit:** Inspects `_dmarc.[domain]` TXT records to confirm policy enforcement (`p=none`, `p=quarantine`, or `p=reject`) and reporting addresses (`rua`/`ruf`).

==== 2. Anti-Spoofing & Phishing Defense Check ====
Ensure that strict DMARC policies (`p=quarantine` or `p=reject`) alongside SPF and DKIM alignment are configured to prevent bad actors from forging emails using your domain.
  * *For detailed anti-spoofing strategies, see [[email:security:spoofing|Email Spoofing]] and [[email:security:phishing|Phishing]].*

==== 3. Disposable Domain Screening ====
Detect whether incoming user registrations or form submissions utilize temporary, disposable email services (e.g., 10-Minute Mail, Guerrilla Mail) to prevent fraud and maintain clean user databases.

==== 4. Email Deliverability Troubleshooting ====
Pinpoint missing or malformed DNS authentication records when outbound emails are rejected by Gmail, Outlook, or Yahoo with [[email:troubleshooting:bounces|SMTP 550 / 5.7.1 Bounce Errors]].

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===== Related Documentation & Tools =====

  * [[tools:dnscheck|Telenegar DNS Check Tool]] — Query raw DNS records (`A`, `MX`, `TXT`, `PTR`) and verify global propagation.
  * [[tools:sitecheck|Telenegar Site Check Tool]] — Audit website availability, redirects, and SSL/TLS certificate health.
  * [[email:troubleshooting:email-deliverability|Email Deliverability Guide]] — Best practices for maintaining sender reputation and inbox placement.
  * [[email:dns-configuration:spf|SPF]] | [[email:dns-configuration:dkim|DKIM]] | [[email:dns-configuration:dmarc|DMARC]] — Core email authentication configuration guides.
  * [[email:security:spoofing|Email Spoofing]] — Prevent domain forgery and unauthorized email transmission.
  * [[email:security:phishing|Phishing]] — Protect users and brands against malicious email campaigns.