Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
strongbox.co
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-19 08:29:29 UTC · ↺ Refresh
MX Hostnames
- strongbox-co.mail.protection.outlook.com
MX Priorities
- strongbox-co.mail.protection.outlook.com: 0
A / AAAA Records
- 199.16.172.138 (no PTR)
Mail Server IPs
- 52.101.9.20 ↩ mail-bl0pr02cu00604.inbound.protection.outlook.com
- 40.93.192.4 ↩ mail-dm2pr04cu00404.inbound.protection.outlook.com
- 52.101.9.12 ↩ mail-bl0pr05cu00504.inbound.protection.outlook.com
- 52.101.9.24 ↩ mail-bl2pr02cu00400.inbound.protection.outlook.com
- 2a01:111:f403:c946::1 ↩ mail-ch1pr04cu00101.inbound.protection.outlook.com
- 2a01:111:f403:c927:: ↩ mail-bn6pr21cu00500.inbound.protection.outlook.com
- 2a01:111:f403:f805::1 ↩ mail-co1pr03cu00301.inbound.protection.outlook.com
- 2a01:111:f403:f908:: ↩ mail-bn1pr21cu00100.inbound.protection.outlook.com
SOA Record
Raw SOA
aspen.ns.cloudflare.com dns.cloudflare.com 2396403405 10000 2400 604800 1800
Primary NS (mname)
aspen.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2396403405
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
igor.ns.cloudflare.com
aspen.ns.cloudflare.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
✓ 3 found
selector1._domainkey
selector2._domainkey
default._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
1 record- SPFv=spf1 include:spf.protection.outlook.com -all
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