Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
colburnschool.edu
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-21 10:20:43 UTC · ↺ Refresh
MX Hostnames
- colburnschool-edu.mail.protection.outlook.com
MX Priorities
- colburnschool-edu.mail.protection.outlook.com: 0
A / AAAA Records
- 141.193.213.10 (no PTR)
- 141.193.213.11 (no PTR)
Mail Server IPs
- 52.101.41.183 ↩ mail-byapr04cu00307.inbound.protection.outlook.com
- 52.101.42.16 ↩ mail-co1pr05cu00300.inbound.protection.outlook.com
- 52.101.41.180 ↩ mail-byapr04cu00204.inbound.protection.outlook.com
- 52.101.11.3 ↩ mail-sn1pr0501cu00103.inbound.protection.outlook.com
- 2a01:111:f403:c801::1 ↩ mail-sn1pr0501cu00101.inbound.protection.outlook.com
- 2a01:111:f403:f90c:: ↩ mail-sn1pr03cu00100.inbound.protection.outlook.com
- 2a01:111:f403:c902::14 ↩ mail-byapr04cu00204.inbound.protection.outlook.com
- 2a01:111:f403:f902:: ↩ mail-bl2pr04cu00100.inbound.protection.outlook.com
SOA Record
Raw SOA
ns1-32.azure-dns.com azuredns-hostmaster.microsoft.com 2026020301 3600 300 2419200 300
Primary NS (mname)
ns1-32.azure-dns.com
Admin Email (rname)
azuredns-hostmaster@microsoft.com
Serial
2026020301
Refresh
3600s
Retry
300s
Expire
2419200s
Minimum TTL
300s
Nameservers (NS)
ns2-32.azure-dns.net
ns3-32.azure-dns.org
ns4-32.azure-dns.info
ns1-32.azure-dns.com
SPF Record
✓ Strict (-all)
v=spf1 a ip4:23.185.0.1/32 include:spf.protection.outlook.com include:rp.oracleemaildelivery.com -all
📊 DNS lookups: 3/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; sp=reject; ruf=mailto:[email protected]; aspf=s; adkim=s
✓ Reject — strongest protection
📋 SPF alignment: Strict
· DKIM alignment: Strict
⚠ No aggregate reports (rua= not set)
↳ Subdomain policy: reject
DKIM Selectors
✓ 5 found
selector1._domainkey
selector2._domainkey
mail._domainkey
s1._domainkey
s2._domainkey
✓ Public key: 216 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
4 records- SPFv=spf1 a ip4:23.185.0.1/32 include:spf.protection.outlook.com include:rp.oracleemaildelivery.com -all
- DKIMv=DKIM1;h=sha256;p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA8b8hW3PMWFNcANmVTRkLTPZFo3TPVGj5kf4RjdX2BE6lVgJknD14svs9cSfwL+KoxrXTbYhUhWDxLHcobHfR4dqTdKkVrHIOBPaZr6VoD+PzD1T7AE9oBSd9GJw3xACnGKVq0DWoKYrYr6tQV4iCv1CNdd2RajaaERZ1tpdpTrL0XADcAvHhlbYzjaBgQHKgfFt8+ARdYtXlFCq13szc1KaiNu6bdJQOFdR7xRnugmWEgiCKaoGJuIOE80V61RgiTMAkX7g5GWJgDajg/k/fXCrNsfeyC9xujs1wrZ7CaAA3vMzrqni3muw5Fp9Waw5I0Li4U43eBzwCYWT
- brevo-code:8c216c7968ea70164f71055b14096fea
- google-site-verification=4fNgIPye5DxmzBn4aNVzLB2V1IeYYW8FVAGNQFWvYJY
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