c3.co

Valid Email Server
Domain Lookup › c3.co

Domain Overview

DNS: ✓ 2mo ago Checker: ✓ 2mo ago
c3.co
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No

Checked via [email protected] · 2026-03-18 19:19:42 UTC · ↺ Refresh

MX Hostnames

  • mx03.hornetsecurity.com
  • mx04.hornetsecurity.com
  • mx02.hornetsecurity.com
  • mx01.hornetsecurity.com

MX Priorities

  • mx02.hornetsecurity.com: 20
  • mx03.hornetsecurity.com: 30
  • mx04.hornetsecurity.com: 40
  • mx01.hornetsecurity.com: 10

A / AAAA Records

  • 185.175.196.2 (no PTR)
  • 2a00:1c98:60:1010::1c09:4203 (no PTR)

Mail Server IPs

  • 94.100.136.8 ↩ mx02.hornetsecurity.com
  • 94.100.134.8 ↩ mx03.hornetsecurity.com
  • 94.100.136.7 ↩ mx04.hornetsecurity.com
  • 94.100.132.8 ↩ mx01.hornetsecurity.com

SOA Record

Raw SOA ns55.domaincontrol.com dns.jomax.net 2026030401 28800 7200 604800 600
Primary NS (mname)
ns55.domaincontrol.com
Admin Email (rname)
dns@jomax.net
Serial
2026030401
Refresh
28800s
Retry
7200s
Expire
604800s
Minimum TTL
600s

Nameservers (NS)

ns55.domaincontrol.com
ns56.domaincontrol.com

SPF Record

✓ Soft Fail (~all)
v=spf1 a mx include:spf.hornetsecurity.com include:mailgun.org include:amazonses.com include:spf.protection.outlook.com ~all
📊 DNS lookups: 6/10
~ Soft fail (~all) — moderate enforcement

DMARC Record

✗ Missing

No DMARC record — emails cannot be rejected on auth failure.

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

15 records
  • apple-domain-verification=COBXRvegyRXdVy8B
  • adobe-idp-site-verification=2e20524b-014a-47c1-95cb-b3f5df7394b8
  • miro-verification=e2525e8f185a525c6240a3ca15be5f6d0805c9d9
  • have-i-been-pwned-verification=5637e254b61146ed95b65da4f24e84b2
  • pardot921853=701f29fb66022793efce465d07b2e1f00cfc6ba01a8d4df6b3a386cf8316e550
  • gIB8PIK/uAmR/wbsAz26ivOIxXNX5qGC0Mw9rf8p5Xr2Q8EXl5vNp2J6h6YHFIBQyb4GG3O5ukFW6rY9CA4N1w==
  • jamf-site-verification=hjc3kPXzhPxTXCcfmZymDQ
  • MS=ms96278348
  • google-site-verification=sY80B0GyGNDoyZPCa7TnpBr0LuwJ1p4Bc5q5k7HHhIY
  • 1password-site-verification=FX2ZUHXZNNE2RGQBOZHJ4UDSU4
  • _telesec-domain-validation=282242_2020-07-08_NyOmsTvpzbz0IJnbc4zgegf3CCxLleJ3p52HJZFfnS5wRndpTK
  • SPFv=spf1 a mx include:spf.hornetsecurity.com include:mailgun.org include:amazonses.com include:spf.protection.outlook.com ~all
  • atlassian-sending-domain-verification=f09270cd-f7ed-4e31-996b-b3a86b99f01f
  • adobe-idp-site-verification=8ac79a93ad164c071a0bde13f79940a166cb845d4ab563620d3bfe98fb24f408
  • atlassian-domain-verification=KQgFZA53Dq3wabYwh/UQCr9xahyxvg0F/iFVsD3Nwi3KFgqQa9PbLjdDXasRDz2L
Full email verification for c3.co

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