Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
c4builders.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-19 11:57:37 UTC · ↺ Refresh
MX Hostnames
- c4builders-com.mail.protection.outlook.com
MX Priorities
- c4builders-com.mail.protection.outlook.com: 0
A / AAAA Records
- 192.231.249.118 ↩ nile.viviotech.net
Mail Server IPs
- 52.101.50.10 ↩ mail-mw2pr02cu00502.inbound.protection.outlook.com
- 52.101.41.183 ↩ mail-byapr04cu00307.inbound.protection.outlook.com
- 52.101.41.4 ↩ mail-sj2pr05cu00204.inbound.protection.outlook.com
- 52.101.9.26 ↩ mail-bl0pr02cu00702.inbound.protection.outlook.com
- 2a01:111:f403:c931:: ↩ mail-sn1pr02cu00100.inbound.protection.outlook.com
- 2a01:111:f403:f907::1 ↩ mail-dm1pr04cu00201.inbound.protection.outlook.com
- 2a01:111:f403:c91d::b ↩ mail-mw2pr02cu00603.inbound.protection.outlook.com
- 2a01:111:f403:f90a:: ↩ mail-bn6pr02cu00300.inbound.protection.outlook.com
SOA Record
Raw SOA
ns03.domaincontrol.com dns.jomax.net 2025082901 28800 7200 604800 600
Primary NS (mname)
ns03.domaincontrol.com
Admin Email (rname)
dns@jomax.net
Serial
2025082901
Refresh
28800s
Retry
7200s
Expire
604800s
Minimum TTL
600s
Nameservers (NS)
ns04.domaincontrol.com
ns03.domaincontrol.com
SPF Record
✓ Soft Fail (~all)
v=spf1 include:spf.protection.outlook.com include:spf.constantcontact.com ~all
📊 DNS lookups: 2/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; rua=mailto:[email protected];
✓ Reject — strongest protection
📋 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
3 records- SPFv=spf1 include:spf.protection.outlook.com include:spf.constantcontact.com ~all
- apple-domain-verification=kaEVlkNIZjOuHSFA
- apple-domain-verification=u8rOMztKYD226U4x
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