challenge.org

Valid Email Server
Domain Lookup › challenge.org

Domain Overview

DNS: ✓ 2mo ago Checker: ✓ 2mo ago
challenge.org
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No

Checked via [email protected] · 2026-03-18 07:13:12 UTC · ↺ Refresh

MX Hostnames

  • challenge-org.mail.protection.outlook.com

MX Priorities

  • challenge-org.mail.protection.outlook.com: 0

A / AAAA Records

  • 194.110.243.195 ↩ ldex1-plesk4.uk.fi.net.uk
  • 2a00:b980:3:11::7 (no PTR)

Mail Server IPs

  • 52.101.73.6 ↩ mail-am6pr04cu00306.inbound.protection.outlook.com
  • 52.101.73.8 ↩ mail-am0pr04cu00500.inbound.protection.outlook.com
  • 52.101.73.11 ↩ mail-am1pr04cu00103.inbound.protection.outlook.com
  • 52.101.68.12 ↩ mail-db9pr02cu00204.inbound.protection.outlook.com
  • 2a01:111:f403:ca09::6 ↩ mail-am4pr0401cu00106.inbound.protection.outlook.com
  • 2a01:111:f403:ca09:: ↩ mail-am3pr04cu00500.inbound.protection.outlook.com
  • 2a01:111:f403:ca09::2 ↩ mail-am0pr83cu00402.inbound.protection.outlook.com
  • 2a01:111:f403:ca04::f ↩ mail-db7pr03cu00507.inbound.protection.outlook.com

SOA Record

Raw SOA one.freethought-dns.uk karveh.challenge.org 2025080401 10800 3600 604800 10800
Primary NS (mname)
one.freethought-dns.uk
Admin Email (rname)
karveh@challenge.org
Serial
2025080401
Refresh
10800s
Retry
3600s
Expire
604800s
Minimum TTL
10800s

Nameservers (NS)

three.freethought-dns.net
two.freethought-dns.com
one.freethought-dns.uk
ldex1-plesk4.uk.fi.net.uk

SPF Record

✓ Strict (-all)
v=spf1 include:spf.LDeX1-Plesk4.uk.fi.net.uk include:spf.protection.outlook.com include:marketheroSPF.smtp.com -all
📊 DNS lookups: 3/10
✓ Hard fail (-all) — strict enforcement

DMARC Record

✗ p=none
v=DMARC1; p=none
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed · DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)

DKIM Selectors

✗ None detected

No DKIM records found for common selectors — your provider may use a custom selector name.

Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses

All TXT Records

1 record
  • SPFv=spf1 include:spf.LDeX1-Plesk4.uk.fi.net.uk include:spf.protection.outlook.com include:marketheroSPF.smtp.com -all
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