Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
501tax.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-19 02:48:37 UTC · ↺ Refresh
MX Hostnames
- 501tax-com.mail.protection.outlook.com
MX Priorities
- 501tax-com.mail.protection.outlook.com: 0
A / AAAA Records
- 162.255.119.70 (no PTR)
Mail Server IPs
- 52.101.42.16 ↩ mail-co1pr05cu00300.inbound.protection.outlook.com
- 52.101.8.44 ↩ mail-dm5pr04cu00104.inbound.protection.outlook.com
- 52.101.10.8 ↩ mail-bn1pr04cu00100.inbound.protection.outlook.com
- 52.101.194.19 ↩ mail-ch5pr02cu00303.inbound.protection.outlook.com
- 2a01:111:f403:f908::1 ↩ mail-bn1pr04cu00101.inbound.protection.outlook.com
- 2a01:111:f403:c922::1 ↩ mail-bl0pr05cu00501.inbound.protection.outlook.com
- 2a01:111:f403:f902:: ↩ mail-bl2pr04cu00100.inbound.protection.outlook.com
- 2a01:111:f403:c946::2 ↩ mail-ch4pr04cu00102.inbound.protection.outlook.com
SOA Record
Raw SOA
dns1.registrar-servers.com hostmaster.registrar-servers.com 1768333399 43200 3600 604800 3601
Primary NS (mname)
dns1.registrar-servers.com
Admin Email (rname)
hostmaster@registrar-servers.com
Serial
1768333399
Refresh
43200s
Retry
3600s
Expire
604800s
Minimum TTL
3601s
Nameservers (NS)
dns2.registrar-servers.com
dns1.registrar-servers.com
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ MissingNo DMARC record — emails cannot be rejected on auth failure.
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._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
2 records- SPFv=spf1 include:spf.protection.outlook.com -all
- box-domain-verification=103f239975701b0435828c44ca0f797de70644076dbf49590a543e5340767098
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