Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
u31.co
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-29 22:35:09 UTC · ↺ Refresh
MX Hostnames
- u31-co.mail.protection.outlook.com
MX Priorities
- u31-co.mail.protection.outlook.com: 10
A / AAAA Records
- 104.19.154.92 (no PTR)
Mail Server IPs
- 52.101.192.1 ↩ mail-yqzpr01cu01001.inbound.protection.outlook.com
- 52.101.190.1 ↩ mail-yt3pr01cu00701.inbound.protection.outlook.com
- 52.101.190.2 ↩ mail-yt3pr01cu00602.inbound.protection.outlook.com
- 52.101.192.0 ↩ mail-yqzpr01cu00900.inbound.protection.outlook.com
- 2a01:111:f403:c942::1 ↩ mail-yt3pr01cu00701.inbound.protection.outlook.com
- 2a01:111:f403:c942::2 ↩ mail-yt3pr01cu00602.inbound.protection.outlook.com
- 2a01:111:f403:c942:: ↩ mail-yt5pr01cu00100.inbound.protection.outlook.com
- 2a01:111:f403:c944:: ↩ mail-yqzpr01cu00900.inbound.protection.outlook.com
SOA Record
Raw SOA
ns-1403.awsdns-47.org awsdns-hostmaster.amazon.com 1 7200 900 1209600 86400
Primary NS (mname)
ns-1403.awsdns-47.org
Admin Email (rname)
awsdns-hostmaster@amazon.com
Serial
1
Refresh
7200s
Retry
900s
Expire
1209600s
Minimum TTL
86400s
Nameservers (NS)
ns-1839.awsdns-37.co.uk
ns-73.awsdns-09.com
ns-916.awsdns-50.net
ns-1403.awsdns-47.org
SPF Record
✓ Soft Fail (~all)
v=spf1 include:spf.protection.outlook.com ip4:142.112.72.172 ~all
📊 DNS lookups: 1/10
~ Soft fail (~all) — moderate 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
✓ 3 found
selector1._domainkey
selector2._domainkey
dkim._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
1 record- SPFv=spf1 include:spf.protection.outlook.com ip4:142.112.72.172 ~all
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