Mail domain report: houten.nl

SPF

pass

SPF record published

Found

Record: v=spf1 include:spf.protection.outlook.com include:_spf.cobytes.email include:spf.protection.outlook.com include:_spf.services.centric.eu include:_spf.zivver.com include:spf.eprov.nl include:spf.simgroephosting.nl include:_spf.emply.com include:spf.mailjet.com include:spf2.houten.nl ip4:213.206.209.14 -all
DNS lookups: 10 of 10
Void lookups: 0 of 2

Checks

✓ No deprecated ptr mechanism #1

No ptr mechanism found in SPF record.
✓ 10 of 10 DNS lookups #2

SPF record needs 10 DNS lookups (limit is 10).
✓ Ends with -all #3

SPF record properly uses -all to restrict unauthorized senders.
✓ Record published #6

SPF record exists for this domain.
✓ Single record #16

Exactly one SPF record is published.
✓ Valid syntax #25

All SPF mechanisms and modifiers are valid.
✓ No void lookups #26

All include/redirect targets exist.
✓ No overly broad IP ranges #27

All ip4/ip6 ranges are narrow enough.

DMARC

pass

p=reject (_dmarc.houten.nl)

Found

Record: v=DMARC1; p=reject; sp=reject; rua=mailto:watchdog5@watchdog.kevlarr.io,mailto:rua@dmarc.brevo.com; adkim=r; aspf=r;
Found at: _dmarc.houten.nl
External report address: mailto:watchdog5@watchdog.kevlarr.io (authorized)
External report address: mailto:rua@dmarc.brevo.com (authorized)

Tag	Value	Meaning
v	DMARC1	Version
p	reject	Policy
sp	reject	Subdomain policy
rua	mailto:watchdog5@watchdog.kevlarr.io,mailto:rua@dmarc.brevo.com	Aggregate report addresses
adkim	r	DKIM alignment (r = relaxed, s = strict)
aspf	r	SPF alignment (r = relaxed, s = strict)

Checks

✓ Policy: reject #4

DMARC policy is set to 'reject', which provides the strongest protection against email spoofing.
✓ Record published #5

DMARC record exists for this domain.
✓ Valid syntax #17

DMARC record syntax is valid.
✓ Applies to 100% of mail #18

DMARC policy applies to all failing mail.
✓ Aggregate reports enabled #19

Aggregate reports are sent to: mailto:watchdog5@watchdog.kevlarr.io, mailto:rua@dmarc.brevo.com
✓ Subdomain policy: reject #20

Subdomains are covered by policy 'reject'.
✓ External report addresses authorized #29

Report addresses in other domains have published their authorization.

DKIM

warn

Selectors: k1, selector1, selector2

Found

Selectors: k1, selector1, selector2
_domainkey: NOERROR

Selector	Key	Flags
k1	RSA 1024 bits
selector1	RSA 2048 bits
selector2	RSA 2048 bits

Checks

✓ Keys found: k1, selector1, selector2 #7

DKIM keys found for this domain with selectors: k1, selector1, selector2
!

1024-bit DKIM key

1024-bit RSA keys are the minimum and are considered weak today: k1 (1024 bits). Rotate to a 2048-bit key.

#23
✓ No problematic flags #24

No keys in test mode, revoked, or limited to SHA-1.

DNSSEC

warn

Signed, DS published at parent

Found

DNSKEY records: Yes (1)
DS at parent: Yes
Algorithms: ECDSAP256SHA256 (13)
Key tags: 30914
Signatures valid until: 29 October 2026, 00:00 UTC

Checks

✓ Signed, DS published at parent #8

DNSSEC is enabled for this domain (DNSKEY and DS present), providing additional security for DNS lookups.
!

Signatures expire in 154h0m0s

DNSKEY signatures expire at 2026-10-29T00:00:00Z (in 154h0m0s). Check that re-signing works.

#21

MX

warn

1 mail server

Found

Priority	Host	Records	Reverse DNS
0	houten-nl.a-v1.mx.microsoft	A 52.101.209.31 A 52.101.209.153 A 52.101.103.143 A 52.101.91.159 AAAA 2a01:111:f403:ca3c::a AAAA 2a01:111:f403:ca04::10 AAAA 2a01:111:f403:ca21::8 AAAA 2a01:111:f403:ca21::c	mail-cpjpr05cu00207.inbound.protection.outlook.com ✓ mail-cpjpr04cu00101.inbound.protection.outlook.com ✓ mail-miypr03cu00107.inbound.protection.outlook.com ✓ mail-matpr04cu00207.inbound.protection.outlook.com ✓ mail-zrxpr07cu00102.inbound.protection.outlook.com ✓ mail-dbapr03cu00100.inbound.protection.outlook.com ✓ mail-matpr04cu00100.inbound.protection.outlook.com ✓ mail-matpr04cu00204.inbound.protection.outlook.com ✓

Checks

✓ 1 MX record #9

Found 1 MX records for this domain.
✓ All hosts resolve #10

All MX records resolve to valid IP addresses.
✓ All hosts have IPv6 #11

All MX records resolve to IPv6 addresses.
!

Single MX host, no backup

Only one MX record found. For better email reliability, consider adding at least one backup MX server.

#12
✓ At most 5 MX records #13

Found 1 MX records, which is within the recommended range (1-5).
✓ No localhost targets #14

No MX records pointing to localhost found.
✓ No private IP addresses #15

No MX records resolving to private IP addresses found.
✓ No CNAME targets #22

No MX records point to a CNAME.
✓ Reverse DNS confirmed #30

All 8 MX addresss have a PTR record that resolves back to them.

TLS

warn

no MTA-STS · no TLS-RPT · DANE on 1 of 1 MX hosts

Found

DANE (TLSA records)

MX host	TLSA	DNSSEC
houten-nl.a-v1.mx.microsoft	3 1 1 803f7447cc75b208… 2 0 1 ea7a25255d111fc3… 3 1 1 54883cc5f1849331… 3 1 1 cfd68bde4129c00a… 2 0 1 c1ad7778796d20bc…	Yes

Lookup error: DNS query for _mta-sts.houten.nl failed: read udp 46.225.38.91:55783->8.8.8.8:53: i/o timeout

Checks

i

Could not be checked

The MTA-STS lookup failed, so this could not be checked: DNS query for _mta-sts.houten.nl failed: read udp 46.225.38.91:55783->8.8.8.8:53: i/o timeout

#32
!

Not configured

MTA-STS or DANE is used without TLS-RPT, so you get no reports when senders fail to deliver because of TLS problems. Publish _smtp._tls TXT "v=TLSRPTv1; rua=mailto:...".

#35
✓ DANE on all MX hosts #36

All 1 MX host publish DNSSEC-validated TLSA records.

BIMI

info

No BIMI record

Checks

i

Not configured

BIMI shows your logo next to your mail in supporting mail clients. It requires DMARC enforcement.

#38