mu.nl

Checked 22 October 2026, 14:40 UTC · via 8.8.8.8
!Passed with warnings
23 passed 5 warnings 0 failed 3 info

SPF

pass

SPF record published

Found

Record
v=spf1 a ip4:45.83.234.93 a:smtp.freedom.nl a:server.mu.nl a:badaward.nl include:spf.antispamcloud.com include:spf.protection.outlook.com -all
DNS lookups
6 of 10
Void lookups
0 of 2

Checks

  • ✓ No deprecated ptr mechanism #1
    No ptr mechanism found in SPF record.
  • ✓ 6 of 10 DNS lookups #2
    SPF record needs 6 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

warn

p=quarantine (_dmarc.mu.nl)

Found

Record
v=DMARC1; p=quarantine;
Found at
_dmarc.mu.nl
TagValueMeaning
vDMARC1Version
pquarantinePolicy

Checks

  • !
    Policy: quarantine
    DMARC policy is set to 'quarantine'. Consider upgrading to 'reject' for stronger protection once you've verified legitimate emails are passing authentication.
    #4
  • ✓ 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.
  • !
    No aggregate reports (rua)
    DMARC record has no rua tag, so you receive no aggregate reports about who sends mail as your domain. Add rua=mailto:...
    #19
  • ✓ Subdomain policy: quarantine #20
    Subdomains are covered by policy 'quarantine'.

DKIM

pass

Selectors: mail

Found

Selectors
mail
_domainkey
NOERROR
SelectorKeyFlags
mailRSA 2048 bits

Checks

  • ✓ Keys found: mail #7
    DKIM keys found for this domain with selectors: mail
  • ✓ Strong keys #23
    DKIM keys are strong enough: mail: RSA 2048 bits.
  • ✓ No problematic flags #24
    No keys in test mode, revoked, or limited to SHA-1.

DNSSEC

warn

Not signed

Found

DNSKEY records
No (0)
DS at parent
No

Checks

  • !
    Not enabled
    DNSSEC is not enabled for this domain. Consider enabling DNSSEC to protect against DNS spoofing attacks.
    #8

MX

warn

3 mail servers

Found

PriorityHostRecordsReverse DNS
10mx.spamexperts.comA 149.13.75.27 AAAA 2001:978:2:7::162:100fe1-r3-in.fra02.l.antispamcloud.com ✓ fe1-r3-in.fra02.l.antispamcloud.com ✓
20fallbackmx.spamexperts.euA 149.13.75.27 A 154.59.193.124 A 154.59.104.23 AAAA 2001:978:2:6::f:124 AAAA 2001:978:2:7::162:100 AAAA 2001:978:2:2c::137:100fe1-r3-in.fra02.l.antispamcloud.com ✓ fe3-r3-in.du01.l.antispamcloud.com ✓ fe2-r3-in.ams14.l.antispamcloud.com ✓ fe3-r3-in.du01.l.antispamcloud.com ✓ fe1-r3-in.fra02.l.antispamcloud.com ✓ fe2-r3-in.ams14.l.antispamcloud.com ✓
30lastmx.spamexperts.netA 149.13.75.27 A 38.89.254.156 A 154.59.104.23 A 38.71.16.244 AAAA 2001:550:2:61::2fc:100 AAAA 2001:978:2:7::162:100 AAAA 2001:550:2:3::62:100 AAAA 2001:978:2:2c::137:100fe1-r3-in.fra02.l.antispamcloud.com ✓ fe1-r2-in.ch03.l.antispamcloud.com ✓ fe2-r3-in.ams14.l.antispamcloud.com ✓ fe2-r2-in.la10.l.antispamcloud.com ✓ no PTR fe1-r3-in.fra02.l.antispamcloud.com ✓ fe2-r2-in.la10.l.antispamcloud.com ✓ fe2-r3-in.ams14.l.antispamcloud.com ✓

Checks

  • ✓ 3 MX records #9
    Found 3 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.
  • ✓ Redundant MX hosts #12
    Found 3 MX records, which provides redundancy for email delivery.
  • ✓ At most 5 MX records #13
    Found 3 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.
  • !
    Addresses without reverse DNS
    These MX addresses have no PTR record, which many receivers treat as a spam signal: 2001:550:2:61::2fc:100 (lastmx.spamexperts.net). Ask your hosting provider to set one.
    #30

TLS

warn

no MTA-STS · no TLS-RPT · DANE on 0 of 3 MX hosts

Found

DANE (TLSA records)

MX hostTLSADNSSEC
mx.spamexperts.comnone-
fallbackmx.spamexperts.eunone-
lastmx.spamexperts.netnone-

Checks

  • !
    Not configured
    MTA-STS is not configured, so other mail servers fall back to unencrypted delivery when TLS fails or is stripped by an attacker. Publish a _mta-sts TXT record and a policy at https://mta-sts.<domain>/.well-known/mta-sts.txt.
    #32
  • i
    Not configured
    TLS-RPT lets senders report TLS delivery problems to you. It is most useful together with MTA-STS or DANE.
    #35
  • i
    Not used
    No MX host publishes TLSA records. DANE lets senders verify your mail server's certificate through DNSSEC; it requires DNSSEC on the MX host's zone.
    #36

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