tk.de

Checked 22 October 2026, 00:40 UTC · via 8.8.8.8
!Passed with warnings
23 passed 6 warnings 0 failed 3 info

SPF

pass

SPF record published

Found

Record
v=spf1 mx ip4:193.22.181.142 ip4:193.22.181.143 ip4:193.22.181.155 ip4:193.201.168.38/32 ip4:193.201.168.170/31 ip4:77.73.253.114 ip4:77.73.253.115 ip4:46.28.184.125 ip4:85.199.138.66 ip4:178.77.125.109 ip4:85.237.86.64 ip4:213.61.228.132 ip4:85.237.85.48 ip4:87.230.106.226 ip4:84.246.127.43 ip6:2a01:488:42:1000:57e6:6ae2::/96 include:_spf.general.transactional-mail-a.com include:agenturserver.de include:spf.qb-feedback.com include:spf.mailjet.com include:performind.com include:spf.protection.outlook.com -all
DNS lookups
8 of 10
Void lookups
0 of 2

Checks

  • ✓ No deprecated ptr mechanism #1
    No ptr mechanism found in SPF record.
  • ✓ 8 of 10 DNS lookups #2
    SPF record needs 8 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.tk.de)

Found

Record
v=DMARC1; p=quarantine; pct=100; rua=mailto:dmarc@tk.de; sp=none
Found at
_dmarc.tk.de
TagValueMeaning
vDMARC1Version
pquarantinePolicy
spnoneSubdomain policy
pct100Percentage of mail the policy applies to
ruamailto:dmarc@tk.deAggregate report addresses

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.
  • ✓ Aggregate reports enabled #19
    Aggregate reports are sent to: mailto:dmarc@tk.de
  • !
    Subdomains unprotected (sp=none)
    DMARC subdomain policy is sp=none, so spoofed mail from subdomains is not blocked. Consider sp=quarantine or sp=reject.
    #20
  • ✓ 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

2 mail servers

Found

PriorityHostRecordsReverse DNS
10mail1.tk.deA 193.22.182.130mail1.tk.de ✓
10mail2.tk.deA 193.22.182.131mail2.tk.de ✓

Checks

  • ✓ 2 MX records #9
    Found 2 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: mail1.tk.de, mail2.tk.de
    #11
  • ✓ Redundant MX hosts #12
    Found 2 MX records, which provides redundancy for email delivery.
  • ✓ At most 5 MX records #13
    Found 2 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 2 MX addresss have a PTR record that resolves back to them.

TLS

warn

no MTA-STS · no TLS-RPT · DANE on 0 of 2 MX hosts

Found

DANE (TLSA records)

MX hostTLSADNSSEC
mail1.tk.denone-
mail2.tk.denone-

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