Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
companybooks.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-18 16:59:14 UTC · ↺ Refresh
MX Hostnames
- companybooks-com.mail.protection.outlook.com
MX Priorities
- companybooks-com.mail.protection.outlook.com: 0
A / AAAA Records
- 198.49.23.145 (no PTR)
- 198.185.159.144 (no PTR)
- 198.185.159.145
- 198.49.23.144
Mail Server IPs
- 52.101.9.21 ↩ mail-bl2pr04cu00205.inbound.protection.outlook.com
- 52.101.50.7 ↩ mail-co1pr21cu00207.inbound.protection.outlook.com
- 52.101.9.12 ↩ mail-bl0pr05cu00504.inbound.protection.outlook.com
- 52.101.11.7 ↩ mail-sa9pr04cu00107.inbound.protection.outlook.com
- 2a01:111:f403:c92c::2 ↩ mail-dm2pr04cu00102.inbound.protection.outlook.com
- 2a01:111:f403:c801:: ↩ mail-sa9pr02cu00200.inbound.protection.outlook.com
- 2a01:111:f403:f903:: (no PTR)
- 2a01:111:f403:c902::1 ↩ mail-sj2pr05cu00401.inbound.protection.outlook.com
SOA Record
Raw SOA
dns1.p01.nsone.net hostmaster.nsone.net 1675988673 43200 7200 1209600 3600
Primary NS (mname)
dns1.p01.nsone.net
Admin Email (rname)
hostmaster@nsone.net
Serial
1675988673
Refresh
43200s
Retry
7200s
Expire
1209600s
Minimum TTL
3600s
Nameservers (NS)
dns2.p01.nsone.net
dns3.p01.nsone.net
dns4.p01.nsone.net
ns01.squarespacedns.com
ns02.squarespacedns.com
ns03.squarespacedns.com
ns04.squarespacedns.com
dns1.p01.nsone.net
SPF Record
✓ Strict (-all)
v=spf1 include:secureserver.net -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ MissingNo DMARC record — emails cannot be rejected on auth failure.
DKIM Selectors
✗ None detectedNo DKIM records found for common selectors — your provider may use a custom selector name.
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
2 records- SPFv=spf1 include:secureserver.net -all
- NETORGFT8855886.onmicrosoft.com
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