Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
51fifteen.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-29 18:13:35 UTC · ↺ Refresh
MX Hostnames
- 51fifteen-com.mail.protection.outlook.com
MX Priorities
- 51fifteen-com.mail.protection.outlook.com: 0
A / AAAA Records
- 104.21.76.17 (no PTR)
- 172.67.185.17 (no PTR)
- 2606:4700:3033::6815:4c11
- 2606:4700:3035::ac43:b911
Mail Server IPs
- 52.101.40.4 ↩ mail-cy5pr03cu00204.inbound.protection.outlook.com
- 52.101.41.28 ↩ mail-sj0pr03cu01504.inbound.protection.outlook.com
- 52.101.41.183 ↩ mail-byapr04cu00307.inbound.protection.outlook.com
- 52.101.42.18 ↩ mail-co1pr03cu00302.inbound.protection.outlook.com
- 2a01:111:f403:f90b:: ↩ mail-bn6pr04cu00100.inbound.protection.outlook.com
- 2a01:111:f403:f910:: ↩ mail-cy5pr03cu00300.inbound.protection.outlook.com
- 2a01:111:f403:f804::3 ↩ mail-co1pr03cu00403.inbound.protection.outlook.com
- 2a01:111:f403:f908:: ↩ mail-bn1pr21cu00100.inbound.protection.outlook.com
SOA Record
Raw SOA
casey.ns.cloudflare.com dns.cloudflare.com 2398585527 10000 2400 604800 1800
Primary NS (mname)
casey.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2398585527
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
casey.ns.cloudflare.com
melissa.ns.cloudflare.com
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com include:spf-us.emailsignatures365.com -all
📊 DNS lookups: 2/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none; rua=mailto:[email protected]
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
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
6 records- smartsheet-site-validation=FWlYN7rSX2ucG69vsbj8Ay9HR73IB549
- SPFv=spf1 include:spf.protection.outlook.com include:spf-us.emailsignatures365.com -all
- MS=ms63323513
- amazon-business-verification=9b2f624772d874aa9cb6c01cf46364f2801295acc62b63e51f2b69b7c1f23b20
- apple-domain-verification=9dStsNHdNXwtKst8
- logmein-verification-code=a34e0543-ff38-47f0-ad05-79eaffdedf15
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