Email assessment · methodology v4

Check email infrastructure

The score assesses DNS foundations, email authentication and mail transport only. Websites, HTTP headers, HTML basics and blocklists do not affect email score, rating, coverage or weekly ranking.

Enter only the domain, for example example.com — without https://, a path or an email address.

Each domain can be checked at most once every five minutes. Opening this page does not start a check; anonymous SMTP, mailbox and port scans are excluded. Completed public checks may appear temporarily in the weekly overview with the domain, rating and time. Verified owners can withdraw visibility.

Stored check results

skymail.de

skymail.de

AAA98/100

Coverage 100 %

Assessment profile

public-email-trust-v4

Requested (UTC)

03.11.2026 07:14:40

Earliest refresh (UTC)

03.11.2026 07:19:40

Email findings to review

Specific deviations and unresolved checks from this saved snapshot. Affected fields are shown directly with each finding.

Saved technical finding; details are available in the evidence.

Notice

Cross-check the authoritative DNS zone and affected records with a second resolver.

View finding and evidence dns.wildcard_detected

The DMARC record is valid. The tags pct, ri come from older DMARC specifications and are evaluated only for compatibility.

Notice

Specifically affected

Legacy DMARC tag: pct=100
Legacy DMARC tag: ri=86400

This tag is not used as an effective control in the current DMARC rules. The listed value comes from the saved record; sp is not one of these legacy tags.

Review each compatibility tag from older DMARC specifications using the table. After careful review, pct=100 and unused ri/rf tags can be removed; p, sp, rua and alignment settings remain unchanged.

View finding and evidence dmarc.legacy_tags

No optional BIMI record is published.

Notice

Review the effective SPF, DMARC or BIMI record against the finding code and correct it in a controlled way.

View finding and evidence bimi.not_configured

5 Passed No technical issue detected. View details

3 Information Observed with no immediate action required. View details

0 Improvements Useful improvements without an acute outage. View details

0 Critical findings Relevant errors requiring priority action. View details

0 Not assessed Excluded from the rating because reliable evidence is missing. View details

Three email assessment categories

What was assessed?

Unavailable areas are explicitly identified and never treated as passed.

Open methodology

Domain and DNS

98/100

Nameservers, records, DNSSEC and basic DNS configuration.

Coverage100 % · 2 checks

1 passed1 review0 unresolved

Email authentication

97/100

SPF, DMARC and publicly verifiable sender rules.

Coverage100 % · 3 checks

1 passed2 review0 unresolved

Mail servers and transport

100/100

MX and TLS reporting policies without anonymous port scans.

Coverage100 % · 3 checks

3 passed0 review0 unresolved

Email infrastructure in detail

Which systems receive mail — and which may send it?

Receiving MX servers and outgoing senders are identified separately from the stored DNS evidence.

Mail routes published in DNS

Inbound and outbound mail, shown separately

MX shows where incoming messages go. SPF shows which networks may send for the domain.

Public DNS evidence

Incoming mail

MX targets

mx1.skymail.de Priority 10

IP targets

178.63.251.174

Outgoing mail

SPF-authorized sources

v=spf1 a mx ip4:144.76.234.83 ip4:178.63.251.174 -all

ADefault domain target

Published by skymail.de

SPF authorizes the public A/AAAA addresses of the named host.

MXDefault domain target

Published by skymail.de

SPF authorizes the public addresses of the MX targets.

IP4144.76.234.83

Published by skymail.de

This IPv4 address or network is explicitly authorized as a sender by SPF.

IP4178.63.251.174

Published by skymail.de

This IPv4 address or network is explicitly authorized as a sender by SPF.

Resolved sending endpoints and hostnames

For each individual public sending IP, its PTR name is resolved and forward-checked against the same IP.

144.76.234.83FCrDNS confirmed

SPF origin

skymail.de · IP4skymail.de · A

PTR names and hostnames

mail.skymail.de

Confirmed: mail.skymail.de

178.63.251.174FCrDNS confirmed

SPF origin

skymail.de · IP4skymail.de · MX-ADDRESS

PTR names and hostnames

emg.emailn.de

Confirmed: emg.emailn.de

MX targets describe inbound mail. SPF describes authorized sending sources. A hostname such as mail.example.org is identified as an outbound server only when stored DNS, SPF or monitoring evidence establishes that role.

Email authentication in detail

DMARC record explained in full

The record, protection, tag values, effective defaults and external report authorisation from this check.

DMARC record found

DNS query: _dmarc.skymail.de

DMARC-compliant with a notice

DMARC-compliant with a notice. The record is usable. Review the notices explained below. Effective policy: p=reject

v=DMARC1; p=reject; pct=100; rua=mailto:info@skymail.de,mailto:d-1vvzfgvypg4nglr1ahfbfjuo0c0lzkgt@reports.sendequelle.com; ruf=mailto:info@skymail.de; ri=86400; fo=1

Protection

What protection does this record provide?

Compliance, policy effect, reporting and alignment are assessed separately.

Record and syntax

Valid and unique

Version, order, separators and values were read as an applicable DMARC record.

Protection for the domain

Reject (p=reject) – highest protection

Messages that fail alignment should be rejected.

Protection for subdomains

Reject (p=reject) – highest protection

Messages that fail alignment should be rejected. The value is not explicitly set and is inherited from the domain policy.

Aggregate reports

Configured and authorized

At least one rua recipient is configured; external destinations were checked using the required DNS authorization.

DKIM alignment

Relaxed – default

The same organizational domain is sufficient. This complies with DMARC and is the standardized default.

SPF alignment

Relaxed – default

The same organizational domain is sufficient. This complies with DMARC and is the standardized default.

What do the individual settings mean?

Every explicit tag and default value is explained with its source, assessment and effect.

Tag	Value	Assessment	Meaning
`v`Protocol version	`DMARC1`Set in the record	Valid	Correct DMARC version; must appear first.
`p`Domain policy	`reject`Set in the record	Valid	Messages that fail alignment should be rejected.
`pct`Policy application percentage	`100`Set in the record	Older tag	Older tag for percentage-based application; modern specifications recommend a complete policy without pct.
`rua`Aggregate report recipients	`mailto:info@skymail.de,mailto:d-1vvzfgvypg4nglr1ahfbfjuo0c0lzkgt@reports.sendequelle.com`Set in the record	Valid	Recipients send aggregate DMARC reports to these destinations.
`ruf`Failure report recipients	`mailto:info@skymail.de`Set in the record	Valid	Forensic failure reports may be sent to these destinations; Sendequelle does not process them in the MVP.
`ri`Requested report interval	`86400`Set in the record	Older tag	Older request for a report interval; receiving systems may ignore it.
`fo`Failure report triggers	`1`Set in the record	Valid	Specifies which authentication failures should trigger forensic reports.
`sp`Subdomain policy	`reject`Default value	Valid	Not explicitly set; subdomains inherit the p policy.
`adkim`DKIM alignment	`r`Default value	Valid	Relaxed DKIM alignment: the same organizational domain is sufficient.
`aspf`SPF alignment	`r`Default value	Valid	Relaxed SPF alignment: the same organizational domain is sufficient.

Report recipient authorization

mailto:info@skymail.de Internal – no external authorization required

mailto:d-1vvzfgvypg4nglr1ahfbfjuo0c0lzkgt@reports.sendequelle.com Externally authorized

From the result to the cause

Email findings and evidence

Each finding shows its assessment, impact, recommended action and the stored values on which it is based.

Domain and DNS

Saved technical finding; details are available in the evidence.

dns.wildcard_detected

Notice

Why does this matter?

DNS deviations can affect availability and the reliability of dependent services.

Next useful step

Cross-check the authoritative DNS zone and affected records with a second resolver.

How this finding was determined (12 saved facts)

Saved evidence for Saved technical finding; details are available in the evidence.
Section	Property	Observed value
Check run	Checker version	`1.0.0`
Check run	Check duration	`216 ms`
Observed	Domain	`skymail.de`
Observed	Wildcard detected	`Yes`
Observed	Query name hash	`faf07acd6b8d35abebfd86eec916aea4fa0225d4c01baba423d2a5c27457968a`
Observed	Addresses	`144.76.234.83`
Observed	Lowest TTL	`86.400 seconds (24 hours)`
Observed	Query name hash	`36ce95cbd10988210900322791a9d359548a5dd3041e53a78f0e05cf7947f784`
Observed	Addresses	`144.76.234.83`
Observed	Lowest TTL	`86.400 seconds (24 hours)`
Expected	Wildcard detected	`No`
Technical evidence	Probe count	`2`

Email authentication

The DMARC record is valid. The tags pct, ri come from older DMARC specifications and are evaluated only for compatibility.

dmarc.legacy_tags

Notice

Specifically affected

Legacy DMARC tag: pct=100
Legacy DMARC tag: ri=86400

Why does this matter?

The policy remains readable. Modern DMARC evaluators may ignore these older tags, so their intended effect may not apply.

Next useful step

Review each compatibility tag from older DMARC specifications using the table. After careful review, pct=100 and unused ri/rf tags can be removed; p, sp, rua and alignment settings remain unchanged.

How this finding was determined (32 saved facts)

Saved evidence for The DMARC record is valid. The tags pct, ri come from older DMARC specifications and are evaluated only for compatibility.
Section	Property	Observed value
Specifically affected	Legacy DMARC tag	`pct=100`
Specifically affected	Legacy DMARC tag	`ri=86400`
Check run	Checker version	`1.0.0`
Check run	Check duration	`1670 ms`
Observed	Domain	`skymail.de`
Observed	DNS lookup location	`_dmarc.skymail.de`
Observed	Policy domain	`skymail.de`
Observed	Organizational domain	`skymail.de`
Observed	Discovery	`direct`
Observed	Raw	`v=DMARC1; p=reject; pct=100; rua=mailto:info@skymail.de,mailto:d-1vvzfgvypg4nglr1ahfbfjuo0c0lzkgt@reports.sendequelle.com; ruf=mailto:info@skymail.de; ri=86400; fo=1`
Observed	V	`DMARC1`
Observed	P	`reject`
Observed	Pct	`100`
Observed	Rua	`mailto:info@skymail.de,mailto:d-1vvzfgvypg4nglr1ahfbfjuo0c0lzkgt@reports.sendequelle.com`
Observed	Ruf	`mailto:info@skymail.de`
Observed	Ri	`86400`
Observed	Fo	`1`
Observed	Aggregate uris	`mailto:info@skymail.de, mailto:d-1vvzfgvypg4nglr1ahfbfjuo0c0lzkgt@reports.sendequelle.com`
Observed	Failure uris	`mailto:info@skymail.de`
Observed	Effective policy	`reject`
Observed	Policy fallback	`No`
Observed	Fingerprint	`70783b7ee61fea6af49402538b8ea287d242dc685536ede659b56ddeb19209c1`
Observed	Applied policy	`reject`
Observed	Uri	`mailto:info@skymail.de`
Observed	Destination host	`skymail.de`
Observed	External	`No`
Observed	Status	`internal`
Observed	Uri	`mailto:d-1vvzfgvypg4nglr1ahfbfjuo0c0lzkgt@reports.sendequelle.com`
Observed	Destination host	`reports.sendequelle.com`
Observed	External	`Yes`
Observed	Status	`authorized`
Observed	DNS lookup location	`skymail.de._report._dmarc.reports.sendequelle.com`
Observed	Lowest TTL	`300 seconds`
Observed	Lowest TTL	`300 seconds`

Email authentication

No optional BIMI record is published.

bimi.not_configured

Notice

Why does this matter?

Incomplete policies can affect spoofing protection, report reception or deliverability.

Next useful step

Review the effective SPF, DMARC or BIMI record against the finding code and correct it in a controlled way.

How this finding was determined (32 saved facts)

Saved evidence for No optional BIMI record is published.
Section	Property	Observed value
Check run	Checker version	`2.0.0`
Check run	Check duration	`295 ms`
Observed	Domain	`skymail.de`
Observed	Selector	`default`
Observed	DNS lookup location	`default._bimi.skymail.de`
Observed	Number of records found	`0`
Observed	DNSSEC status	`secure`
Observed	Lowest TTL	`21.600 seconds (6 hours)`
Expected	Optional	`Yes`
Expected	Selector	`default`
Expected	Https logo	`Yes`
Technical evidence	Adapter	`App\Domain\Monitoring\Dns\Consensus\DigTxtResolver`
Technical evidence	DNS lookup location	`default._bimi.skymail.de`
Technical evidence	Minimum agreement	`2`
Technical evidence	Name	`google`
Technical evidence	Server	`8.8.8.8`
Technical evidence	Transport	`tls`
Technical evidence	Tls hostname	`dns.google`
Technical evidence	Status	`secure`
Technical evidence	Reason	`authenticated_data`
Technical evidence	Exit code	`0`
Technical evidence	Timed out	`No`
Technical evidence	Response status	`NOERROR`
Technical evidence	Authenticated data	`Yes`
Technical evidence	Flags	`qr, rd, ra, ad`
Technical evidence	Check duration	`147`
Technical evidence	Number of records found	`1`
Technical evidence	Record fingerprint	`4ff79eccf756a2d3cfd139c324a3bf5ab93037f4edeea2f11d2954c0fcabed8c`
Technical evidence	Lowest TTL	`21.600 seconds (6 hours)`
Technical evidence	Name	`cloudflare`
Technical evidence	Server	`1.1.1.1`
Technical evidence	Transport	`tls`

Domain and DNS

DNS and MX infrastructure is consistent

dns.infrastructure_ok

Passed

Why does this matter?

Nameservers, SOA, MX targets and DNSSEC were evaluated without a higher-priority error.

Next useful step

Keep the configuration and monitor changes.

How this finding was determined (32 saved facts)

Saved evidence for DNS and MX infrastructure is consistent
Section	Property	Observed value
Check run	Checker version	`3.0.0`
Check run	Check duration	`623 ms`
Observed	Resolver used	`system-recursive`
Observed	Nameservers	`ns1.nbiserv.de, ns2.nbiserv.de, ns3.nbiserv.de, ns4.nbiserv.de`
Observed	Mname	`ns.nbiserv.de`
Observed	Rname	`hostmaster.nbiserv.de`
Observed	Serial	`2026050883`
Observed	Refresh	`86400`
Observed	Retry	`7200`
Observed	Expire	`2419200`
Observed	Minimum ttl	`7200`
Observed	Priority	`10`
Observed	Target	`mx1.skymail.de`
Observed	Domain addresses	`144.76.234.83`
Observed	Addresses	`178.63.251.174`
Observed	Status	`secure`
Observed	Reason	`resolver_consensus_secure`
Expected	Nameservers	`at_least_two`
Expected	Soa	`present`
Expected	Mx	`valid_or_null_mx`
Expected	Mx addresses	`public_only`
Expected	Dnssec	`secure_or_explicitly_insecure`
Technical evidence	Adapter	`App\Domain\Monitoring\Dns\Dnssec\DigDnssecValidator`
Technical evidence	Domain	`skymail.de`
Technical evidence	Minimum agreement	`2`
Technical evidence	Name	`google`
Technical evidence	Server	`8.8.8.8`
Technical evidence	Transport	`tls`
Technical evidence	Tls hostname	`dns.google`
Technical evidence	Status	`secure`
Technical evidence	Reason	`authenticated_data`
Technical evidence	Exit code	`0`

Email authentication

SPF policy is consistent

spf.policy_valid

Passed

Why does this matter?

The record and its statically resolvable dependencies are within the evaluated limits.

Next useful step

Continue monitoring changes to sending services and includes.

How this finding was determined (32 saved facts)

Saved evidence for SPF policy is consistent
Section	Property	Observed value
Check run	Checker version	`3.0.0`
Check run	Check duration	`199 ms`
Observed	Domain	`skymail.de`
Observed	Raw	`v=spf1 a mx ip4:144.76.234.83 ip4:178.63.251.174 -all`
Observed	Qualifier	`+`
Observed	Name	`a`
Observed	Qualifier	`+`
Observed	Name	`mx`
Observed	Qualifier	`+`
Observed	Name	`ip4`
Observed	Argument	`144.76.234.83`
Observed	Qualifier	`+`
Observed	Name	`ip4`
Observed	Argument	`178.63.251.174`
Observed	Qualifier	`-`
Observed	Name	`all`
Observed	Dns lookup cost	`2`
Observed	SPF terms causing DNS lookups	`2 out of at most 10 permitted SPF DNS lookups`
Observed	SPF queries without usable records	`0 – no SPF queries without matching usable DNS records were counted`
Observed	Owner	`skymail.de`
Observed	Mechanism	`a`
Observed	Target	`skymail.de`
Observed	Type	`A`
Observed	Resolver used	`system-recursive`
Observed	Values	`144.76.234.83`
Observed	Void	`No`
Observed	Owner	`skymail.de`
Observed	Mechanism	`a`
Observed	Target	`skymail.de`
Observed	Type	`AAAA`
Observed	Resolver used	`system-recursive`
Observed	Void	`Yes`

Mail servers and transport

MTA-STS policy is consistent

mta.policy_valid

Passed

Why does this matter?

The TXT announcement, HTTPS policy and MX coverage were evaluated successfully.

Next useful step

Monitor the policy ID and certificates when making changes.

How this finding was determined (32 saved facts)

Saved evidence for MTA-STS policy is consistent
Section	Property	Observed value
Check run	Checker version	`1.0.0`
Check run	Check duration	`232 ms`
Observed	Domain	`skymail.de`
Observed	DNS lookup location	`_mta-sts.skymail.de`
Observed	Policy host	`mta-sts.skymail.de`
Observed	Version	`STSv1`
Observed	Fingerprint	`88815d825386d1bb25bc1189ea0ff761e728bf9a24d48fc854bf079b52f9574a`
Observed	Version	`STSv1`
Observed	Mode	`testing`
Observed	Mx	`filter.emailn.de, mx1.skymail.de`
Observed	Max age	`86400`
Observed	Body sha256	`990ed4335149a421c2465bbc440d19fa67808e9d8fbd34cd4b25cdf325c19bd9`
Observed	Mx hosts	`mx1.skymail.de`
Expected	Policy required	`No`
Expected	Url	`https://mta-sts.skymail.de/.well-known/mta-sts.txt`
Expected	Redirects	`0`
Expected	Https port	`443`
Expected	Max bytes	`65536`
Technical evidence	Adapter	`App\Domain\Monitoring\MtaSts\NativeMtaStsDnsResolver`
Technical evidence	Resolver used	`system-recursive`
Technical evidence	DNS lookup location	`_mta-sts.skymail.de`
Technical evidence	Txt record count	`1`
Technical evidence	Mx hosts	`mx1.skymail.de`
Technical evidence	Adapter	`App\Domain\Monitoring\MtaSts\PinnedMtaStsPolicyFetcher`
Technical evidence	Policy host	`mta-sts.skymail.de`
Technical evidence	Path	`/.well-known/mta-sts.txt`
Technical evidence	Resolved addresses	`144.76.234.83`
Technical evidence	Selected address	`144.76.234.83`
Technical evidence	Ip family	`ipv4`
Technical evidence	Final HTTP status	`200`
Technical evidence	Content type	`text/plain`
Technical evidence	Response bytes	`87`

Mail servers and transport

TLS-RPT policy is consistent

tlsrpt.policy_valid

Passed

Why does this matter?

The record and reporting destinations were evaluated syntactically and semantically.

Next useful step

Monitor incoming reports and policy changes.

How this finding was determined (32 saved facts)

Saved evidence for TLS-RPT policy is consistent
Section	Property	Observed value
Check run	Checker version	`2.0.0`
Check run	Check duration	`253 ms`
Observed	Domain	`skymail.de`
Observed	DNS lookup location	`_smtp._tls.skymail.de`
Observed	Number of records found	`1`
Observed	Raw	`v=TLSRPTv1; rua=mailto:t-zrqbvji6agd84of3lyrzfqftjhlf3ch9@reports.sendequelle.com`
Observed	V	`TLSRPTv1`
Observed	Rua	`mailto:t-zrqbvji6agd84of3lyrzfqftjhlf3ch9@reports.sendequelle.com`
Observed	Aggregate uris	`mailto:t-zrqbvji6agd84of3lyrzfqftjhlf3ch9@reports.sendequelle.com`
Observed	Fingerprint	`33d3456b194e542728ec84f550c0f54e62ce251989a03f8c627106520704bb21`
Observed	Lowest TTL	`3.600 seconds (1 hours)`
Observed	DNSSEC status	`secure`
Expected	Number of records found	`1`
Expected	Policy required	`No`
Technical evidence	Adapter	`App\Domain\Monitoring\Dns\Consensus\DigTxtResolver`
Technical evidence	DNS lookup location	`_smtp._tls.skymail.de`
Technical evidence	Minimum agreement	`2`
Technical evidence	Name	`google`
Technical evidence	Server	`8.8.8.8`
Technical evidence	Transport	`tls`
Technical evidence	Tls hostname	`dns.google`
Technical evidence	Status	`secure`
Technical evidence	Reason	`authenticated_data`
Technical evidence	Exit code	`0`
Technical evidence	Timed out	`No`
Technical evidence	Response status	`NOERROR`
Technical evidence	Authenticated data	`Yes`
Technical evidence	Flags	`qr, rd, ra, ad`
Technical evidence	Check duration	`118`
Technical evidence	Number of records found	`1`
Technical evidence	Record fingerprint	`aaa6808113546f4ec394a50e3a1d5e68901703870105260142133e0eba0d8f2b`
Technical evidence	Lowest TTL	`3.600 seconds (1 hours)`

Mail servers and transport

The MX RRset and the SMTP TLSA policies of every MX host are DNSSEC validated. No certificate matching was performed by this public check.

public.dane_policy_published

Passed

Why does this matter?

The public check assesses DNSSEC and published TLSA policies at all MX targets. It does not match the current SMTP certificate.

Next useful step

Continue monitoring TLSA and certificate changes for your verified domain.

How this finding was determined (32 saved facts)

Saved evidence for The MX RRset and the SMTP TLSA policies of every MX host are DNSSEC validated. No certificate matching was performed by this public check.
Section	Property	Observed value
Check run	Checker version	`1.0.0`
Check run	Check duration	`425 ms`
Observed	Domain	`skymail.de`
Observed	DNS lookup location	`skymail.de`
Observed	Mx hosts	`mx1.skymail.de`
Observed	Mx dnssec status	`secure`
Observed	Hostname	`mx1.skymail.de`
Observed	DNS lookup location	`_25._tcp.mx1.skymail.de`
Observed	DNSSEC status	`secure`
Observed	State	`published`
Observed	Usage	`3`
Observed	Selector	`1`
Observed	Matching type	`1`
Observed	Association sha256	`166608d46c59da16146ddd32383a886a074619ebd62a4f3cb019d046b392161f`
Observed	Record fingerprint	`5244f514fd34d2bcf5bbfb01b05a11e95d18ac707810319b059bcbd4367b745a`
Observed	Record found	`3 1 1 22c340df62685ea3ba6c00d1b8750e1d4d6590f01fc946c3664da1618e6d85e9`
Observed	Smtp usable	`Yes`
Observed	Lowest TTL	`2.845 seconds`
Observed	Reason	`resolver_consensus_secure`
Observed	Policy state	`published`
Expected	Mx dnssec	`secure`
Expected	Tlsa dnssec	`secure`
Expected	Smtp port	`25`
Expected	Tlsa coverage	`all_mx`
Expected	Certificate match	`authorised_monitor_only`
Technical evidence	Performed	`No`
Technical evidence	Reason	`anonymous_public_tool_boundary`
Technical evidence	Certificate match	`not_checked`
Technical evidence	Query type	`MX`
Technical evidence	Minimum agreement	`2`
Technical evidence	Name	`google`
Technical evidence	Server	`8.8.8.8`

Supplementary information with no effect on the email assessment

Website, HTTP security headers, HTML basics and blocklists are shown separately. Their local warnings are not email score deductions.

Web security headers

Basic web security headers are missing or not unambiguously effective.

public.headers_incomplete

Notice

Supplementary finding · no score effect

Specifically affected

Missing or not effective: Permissions-Policy

Why does this matter?

Missing browser protection directives increase the website attack surface.

Next useful step

Add missing headers on the server; validate CSP in report-only mode first.

How this finding was determined (5 saved facts)

Saved evidence for Basic web security headers are missing or not unambiguously effective.
Section	Property	Observed value
Specifically affected	Missing or not effective	`Permissions-Policy`
Check run	Checker version	`2.0.0`
Technical evidence	Analyzed destination page	`https://skymail.de/`
Technical evidence	Present	`hsts, csp, frame_protection, nosniff, referrer_policy`
Technical evidence	Missing	`permissions_policy`
Technical evidence	Checked properties	`6`

HTML basics

The automatically checked HTML basics are present.

public.accessibility_basics_present

Passed

Supplementary finding · no score effect

Why does this matter?

This check did not identify a specific deficiency.

Next useful step

Keep the configuration and check it again regularly.

How this finding was determined (5 saved facts)

Saved evidence for The automatically checked HTML basics are present.
Section	Property	Observed value
Check run	Checker version	`2.0.0`
Technical evidence	Analyzed destination page	`https://skymail.de/`
Technical evidence	Present	`language, title, viewport, single_h1, main_landmark`
Technical evidence	Checked properties	`5`
Technical evidence	Complete WCAG audit	`No`

Blocklists and reputation

The blocklist provider did not return a reliable assessment.

public.reputation_unavailable

Not assessed

Supplementary finding · no score effect

Why does this matter?

No blocklist or reputation rating is claimed without reliable provider evidence.

Next useful step

The operator should check provider configuration and availability before repeating this assessment.

How this finding was determined (32 saved facts)

Saved evidence for The blocklist provider did not return a reliable assessment.
Section	Property	Observed value
Check run	Checker version	`3.0.0`
Observed	IP address	`144.76.234.83`
Observed	Ip family	`ipv4`
Observed	Reputation provider	`multi-provider`
Observed	Provider status	`unavailable`
Observed	Complete	`No`
Observed	Checked at	`2026-11-03T07:14:46+00:00`
Observed	Checked lists	`0`
Observed	Lists with a match	`0`
Observed	Unavailable lists	`5`
Observed	Policy advisories	`0`
Observed	Key	`spamhaus_zen`
Observed	Name	`Spamhaus ZEN`
Observed	Status	`unavailable`
Observed	Category	`unknown`
Observed	Checked at	`2026-11-03T07:14:46+00:00`
Observed	Source	`https://www.spamhaus.org/blocklists/zen-blocklist/`
Observed	Delisting url	`https://check.spamhaus.org/`
Observed	Reason code	`provider_disabled`
Observed	Key	`abusix_guardian`
Observed	Name	`Abusix Guardian`
Observed	Status	`unavailable`
Observed	Category	`unknown`
Observed	Checked at	`2026-11-03T07:14:46+00:00`
Observed	Source	`https://abusix.com/guardian/`
Observed	Delisting url	`https://lookup.abusix.com/`
Observed	Reason code	`provider_disabled`
Observed	Key	`spamcop`
Observed	Name	`SpamCop Blocking List`
Observed	Status	`unavailable`
Observed	Category	`unknown`
Observed	Checked at	`2026-11-03T07:14:46+00:00`

Website and TLS

The HTTPS connection was successfully verified.

public.https_verified

Passed

Supplementary finding · no score effect

Why does this matter?

This check did not identify a specific deficiency.

Next useful step

Keep the configuration and check it again regularly.

How this finding was determined (13 saved facts)

Saved evidence for The HTTPS connection was successfully verified.
Section	Property	Observed value
Check run	Checker version	`2.0.0`
Technical evidence	Requested URL	`https://skymail.de/`
Technical evidence	Final URL	`https://skymail.de/`
Technical evidence	Validated destination host	`skymail.de`
Technical evidence	Final HTTP status	`200`
Technical evidence	Ip family	`ipv4`
Technical evidence	Certificate and hostname verified	`Yes`
Technical evidence	TLS protocol	`TLSv1.3`
Technical evidence	TLS cipher	`TLS_AES_256_GCM_SHA384`
Technical evidence	Certificate valid until	`2026-12-28T08:28:57+00:00`
Technical evidence	Certificate time remaining	`55`
Technical evidence	Check duration	`67`
Technical evidence	Safely followed redirects	`0`

Website connection in detail

Understand the HTTPS and TLS assessment

Final status, certificate verification, negotiated connection and every safely followed redirect from this snapshot.

Measured HTTPS connection

TLS, certificate and redirect destination

Every displayed assessment is based on this saved check.

Safe external check

Final HTTPS status

HTTP 200

The safely followed destination was reachable.

Certificate and hostname

Verified

The certificate chain and hostname binding were accepted for this specific HTTPS connection.

Negotiated protocol

TLSv1.3

Measured on the final HTTPS connection; this does not describe every supported protocol.

Negotiated cipher suite

TLS_AES_256_GCM_SHA384

This is the cipher suite of this connection, not a complete cipher suite scan.

Certificate time remaining

55 days

Recorded expiry: 2026-12-28T08:28:57+00:00

Redirect chain

0 redirects

The requested HTTPS address was the final destination without a redirect.

Safely followed path

https://skymail.de/

Scope limit: The assessment covers the safely resolved, IP-pinned HTTPS connection to the final home page. It is not a complete test of all cipher suites, key types, TLS versions, PQC methods or other ports.

Blocklists and IP reputation

Which mail IP was checked against which lists?

Inbound MX addresses and publicly discoverable SPF sender addresses are shown separately. DKIM does not identify sending IPs; private DMARC sources are not used in this public check.

Partially evaluated

2 Mail IP addresses

0 Selected lists

0 Confirmed hits

10 Unavailable

144.76.234.83 SPF-autorisierte Sender-IP multi-provider Incomplete

Blocklist results for 144.76.234.83
Data source	Classification	Result	Check details	Actions
Abusix Guardian	Technical data source	Unavailable	2026-11-03T07:14:46+00:00 No approved data provider is available for this query. The operator must configure and approve the provider; retrying alone does not close this gap.	Source Open Abusix Guardian in a new window Appeal / delisting Open Abusix Guardian in a new window
Barracuda Reputation Block List	Technical data source	Unavailable	2026-11-03T07:14:46+00:00 No approved data provider is available for this query. The operator must configure and approve the provider; retrying alone does not close this gap.	Source Open Barracuda Reputation Block List in a new window Appeal / delisting Open Barracuda Reputation Block List in a new window
SpamCop Blocking List	Technical data source	Unavailable	2026-11-03T07:14:46+00:00 No approved data provider is available for this query. The operator must configure and approve the provider; retrying alone does not close this gap.	Source Open SpamCop Blocking List in a new window Appeal / delisting Open SpamCop Blocking List in a new window
SpamRATS	Technical data source	Unavailable	2026-11-03T07:14:46+00:00 No approved data provider is available for this query. The operator must configure and approve the provider; retrying alone does not close this gap.	Source Open SpamRATS in a new window Appeal / delisting Open SpamRATS in a new window
Spamhaus ZEN	Technical data source	Unavailable	2026-11-03T07:14:46+00:00 No approved data provider is available for this query. The operator must configure and approve the provider; retrying alone does not close this gap.	Source Open Spamhaus ZEN in a new window Appeal / delisting Open Spamhaus ZEN in a new window

178.63.251.174 MX mx1.skymail.deSPF-autorisierte Sender-IP multi-provider Incomplete

Blocklist results for 178.63.251.174
Data source	Classification	Result	Check details	Actions
Abusix Guardian	Technical data source	Unavailable	2026-11-03T07:14:46+00:00 No approved data provider is available for this query. The operator must configure and approve the provider; retrying alone does not close this gap.	Source Open Abusix Guardian in a new window Appeal / delisting Open Abusix Guardian in a new window
Barracuda Reputation Block List	Technical data source	Unavailable	2026-11-03T07:14:46+00:00 No approved data provider is available for this query. The operator must configure and approve the provider; retrying alone does not close this gap.	Source Open Barracuda Reputation Block List in a new window Appeal / delisting Open Barracuda Reputation Block List in a new window
SpamCop Blocking List	Technical data source	Unavailable	2026-11-03T07:14:46+00:00 No approved data provider is available for this query. The operator must configure and approve the provider; retrying alone does not close this gap.	Source Open SpamCop Blocking List in a new window Appeal / delisting Open SpamCop Blocking List in a new window
SpamRATS	Technical data source	Unavailable	2026-11-03T07:14:46+00:00 No approved data provider is available for this query. The operator must configure and approve the provider; retrying alone does not close this gap.	Source Open SpamRATS in a new window Appeal / delisting Open SpamRATS in a new window
Spamhaus ZEN	Technical data source	Unavailable	2026-11-03T07:14:46+00:00 No approved data provider is available for this query. The operator must configure and approve the provider; retrying alone does not close this gap.	Source Open Spamhaus ZEN in a new window Appeal / delisting Open Spamhaus ZEN in a new window

Scope limit: The result applies only to the named data sources at the displayed check time. It is not a delivery guarantee or proof for or against spam activity.

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Fixed variants without tracking, scripts or external resources.

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The score is an external technical assessment, not a certificate, guarantee, legal review or complete security audit.