opsolder.nl

Checked 22 October 2026, 15:02 UTC · via 8.8.8.8
✗Problems found
24 passed 4 warnings 1 failed 3 info

SPF

fail

SPF record published

Found

Record
v=spf1 mx a include:_spf.relay.mailprotect.be ~all
DNS lookups
4 of 10
Void lookups
0 of 2
Records published
3

Checks

  • ✓ No deprecated ptr mechanism #1
    No ptr mechanism found in SPF record.
  • ✓ 4 of 10 DNS lookups #2
    SPF record needs 4 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.
  • ✗
    Multiple SPF records
    Found 3 SPF records. Publishing more than one v=spf1 record causes a permerror; merge them into a single record.
    #16
  • ✓ 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.opsolder.nl)

Found

Record
v=DMARC1; p=reject; rua=mailto:dmarc@opsolder.nl;
Found at
_dmarc.opsolder.nl
TagValueMeaning
vDMARC1Version
prejectPolicy
ruamailto:dmarc@opsolder.nlAggregate report addresses

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:dmarc@opsolder.nl
  • ✓ Subdomain policy: reject #20
    Subdomains are covered by policy 'reject'.
  • ✓ Report addresses in own domain #29
    All report addresses are in your own organizational domain.

DKIM

warn

Selectors: selector1

Found

Selectors
selector1
_domainkey
NOERROR
SelectorKeyFlags
selector1RSA 1024 bits

Checks

  • ✓ Keys found: selector1 #7
    DKIM keys found for this domain with selectors: selector1
  • !
    1024-bit DKIM key
    1024-bit RSA keys are the minimum and are considered weak today: selector1 (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

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
0opsolder-nl.mail.protection.outlook.comA 52.101.209.31 A 52.101.181.156 A 52.101.68.29 A 52.101.181.153 AAAA 2a01:111:f403:ca38::8 AAAA 2a01:111:f403:ca21::8 AAAA 2a01:111:f403:ca21::a AAAA 2a01:111:f403:ca09::28mail-cpjpr05cu00207.inbound.protection.outlook.com ✓ mail-wa4pr05cu00104.inbound.protection.outlook.com ✓ mail-dbapr03cu00105.inbound.protection.outlook.com ✓ mail-wa4pr04cu00101.inbound.protection.outlook.com ✓ mail-wa4pr04cu00100.inbound.protection.outlook.com ✓ mail-matpr04cu00100.inbound.protection.outlook.com ✓ mail-maspr04cu00102.inbound.protection.outlook.com ✓ mail-am6pr02cu00300.inbound.protection.outlook.com ✓
10mx.mailprotect.beA 178.208.39.140 A 178.208.39.142 A 178.208.39.143 A 178.208.39.141mx.mailprotect.be ✓ mx.mailprotect.be ✓ mx.mailprotect.be ✓ mx.mailprotect.be ✓
50mx.backup.mailprotect.beA 178.208.39.141 A 178.208.39.142 A 178.208.39.143 A 178.208.39.140mx.mailprotect.be ✓ mx.mailprotect.be ✓ mx.mailprotect.be ✓ mx.mailprotect.be ✓

Checks

  • ✓ 3 MX records #9
    Found 3 MX records for this domain.
  • ✓ All hosts resolve #10
    All MX records resolve to valid IP addresses.
  • !
    Hosts without IPv6
    The following MX hosts could not be resolved to IPv6 addresses: mx.mailprotect.be, mx.backup.mailprotect.be
    #11
  • ✓ 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.
  • ✓ Reverse DNS confirmed #30
    All 16 MX addresss have a PTR record that resolves back to them.

TLS

warn

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

Found

DANE (TLSA records)

MX hostTLSADNSSEC
opsolder-nl.mail.protection.outlook.comnone-
mx.mailprotect.benone-
mx.backup.mailprotect.benone-

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