sek.io

Valid Email Server

Domain Overview

DNS: ✓ 2mo ago Checker: ✓ 2mo ago
sek.io
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]

Checked via [email protected] · 2026-04-01 08:34:10 UTC · ↺ Refresh

MX Hostnames

  • sek-io.mail.protection.outlook.com

MX Priorities

  • sek-io.mail.protection.outlook.com: 0

A / AAAA Records

  • 172.64.150.46 (no PTR)
  • 104.18.37.210 (no PTR)
  • 2a06:98c1:310b::ac40:962e
  • 2a06:98c1:310b::6812:25d2

Mail Server IPs

  • 52.101.50.4 ↩ mail-co1pr03cu00404.inbound.protection.outlook.com
  • 52.101.194.3 ↩ mail-ch1pr04cu00103.inbound.protection.outlook.com
  • 52.101.42.18 ↩ mail-co1pr03cu00302.inbound.protection.outlook.com
  • 52.101.10.2 ↩ mail-bn8pr03cu00202.inbound.protection.outlook.com
  • 2a01:111:f403:c91d::b ↩ mail-mw2pr02cu00603.inbound.protection.outlook.com
  • 2a01:111:f403:f90c:: ↩ mail-sn1pr03cu00100.inbound.protection.outlook.com
  • 2a01:111:f403:f913::1 ↩ mail-cy5pr05cu00101.inbound.protection.outlook.com
  • 2a01:111:f403:f910:: ↩ mail-cy5pr03cu00300.inbound.protection.outlook.com

SOA Record

Raw SOA alina.ns.cloudflare.com dns.cloudflare.com 2400503416 10000 2400 604800 1800
Primary NS (mname)
alina.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2400503416
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s

Nameservers (NS)

alina.ns.cloudflare.com
kirk.ns.cloudflare.com

SPF Record

✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com include:mail.zendesk.com ip4:45.176.192.20 ip4:44.227.35.55 ip4:44.225.148.59 ip4:34.209.129.29 include:_spf.salesforce.com include:amazonses.com -all
📊 DNS lookups: 4/10
✓ Hard fail (-all) — strict enforcement

DMARC Record

~ Quarantine
v=DMARC1; p=quarantine; sp=quarantine; adkim=s; aspf=s; rua=mailto:[email protected],mailto:[email protected]; ruf=mailto:[email protected]; fo=1
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Strict · DKIM alignment: Strict
📧 Reports → mailto:[email protected],mailto:[email protected]
↳ Subdomain policy: quarantine

DKIM Selectors

✓ 2 found
selector1._domainkey
selector2._domainkey
✓ Public key: 392 chars (valid)
✓ DKIM properly configured for selector: selector1

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

All TXT Records

8 records
  • google-site-verification=69sGS7aFB1Ra2cuY1wGv2hS68XVFoFj8Wh9b8WsOdpw
  • new-relic-domain-verification=fcb82e38c96842e8a70ba8c7e65c3a36
  • perplexity-ai-domain-verification-1ferne=llfkw7qKafz9W7bRPWuhcp8S6
  • sek-prod2.azurewebsites.net
  • SPFv=spf1 include:spf.protection.outlook.com include:mail.zendesk.com ip4:45.176.192.20 ip4:44.227.35.55 ip4:44.225.148.59 ip4:34.209.129.29 include:_spf.salesforce.com include:amazonses.com -all
  • MS=ms44487620
  • anthropic-domain-verification-m27se6=8sXajAMXXrtbHlDFP1fTGjFMW
  • anthropic-domain-verification-qn3q3c=6yjpo8fIVbKUShpjvTMFs0ff5
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