Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
blackhillscorp.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-23 07:30:44 UTC · ↺ Refresh
MX Hostnames
- blackhillscorp-com.mail.protection.outlook.com
MX Priorities
- blackhillscorp-com.mail.protection.outlook.com: 10
A / AAAA Records
- 20.12.139.137 (no PTR)
Mail Server IPs
- 52.101.194.13 ↩ mail-ch0pr04cu00605.inbound.protection.outlook.com
- 52.101.11.3 ↩ mail-sn1pr0501cu00103.inbound.protection.outlook.com
- 52.101.9.5 ↩ mail-mn2pr04cu00205.inbound.protection.outlook.com
- 52.101.50.7 ↩ mail-co1pr21cu00207.inbound.protection.outlook.com
- 2a01:111:f403:c946::6 ↩ mail-ch5pr02cu00406.inbound.protection.outlook.com
- 2a01:111:f403:f901:: ↩ mail-mn2pr04cu00200.inbound.protection.outlook.com
- 2a01:111:f403:f802::3 ↩ mail-sj0pr03cu01403.inbound.protection.outlook.com
- 2a01:111:f403:c946::1 ↩ mail-ch1pr04cu00101.inbound.protection.outlook.com
SOA Record
Raw SOA
ns1.blackhillscorp.com root.ns1.blackhillscorp.com 2022110901 1200 180 1209600 5
Primary NS (mname)
ns1.blackhillscorp.com
Admin Email (rname)
root@ns1.blackhillscorp.com
Serial
2022110901
Refresh
1200s
Retry
180s
Expire
1209600s
Minimum TTL
5s
Nameservers (NS)
ns2.blackhillscorp.com
ns1.blackhillscorp.com
SPF Record
✓ Strict (-all)
v=spf1 mx ip4:74.116.253.77 ip4:20.112.235.2/31 ip4:20.186.113.184/31 ip4:20.221.65.200/31 ip4:20.57.27.200/31 ip4:20.221.103.65 ip4:20.122.236.144 include:spf.protection.outlook.com -all
📊 DNS lookups: 2/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine; rua=mailto:[email protected]; ruf=mailto:[email protected]; fo=1; pct=100
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 4 found
selector1._domainkey
selector2._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
6 records- OATI iQ9fedL42wd@cD7Vz3fKijz@b2mA86822cU@b2mA86822cU
- uCi1VaNARBj4Av/l2+OuyCu6SsO8k9kB5EVrx4uTRo3d9jZyGA8G0k0GATmKhCARuD+929QK2iaKOkWV8BK8TA==
- _j4tef9k3lj2lq9g8ughp86pof65bbus
- 9TeeYfGHKweXh64LKsC8YVf46EIUxQpckuF+Nq1hVOVqygPDuv/V5paGdEEY02RutELHHs6guuagWu4ZEq2CYg==
- SPFv=spf1 mx ip4:74.116.253.77 ip4:20.112.235.2/31 ip4:20.186.113.184/31 ip4:20.221.65.200/31 ip4:20.57.27.200/31 ip4:20.221.103.65 ip4:20.122.236.144 include:spf.protection.outlook.com -all
- iQ9fedL42wd@cD7Vz3fKijz@b2mA86822cU@b2mA86822cU
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