Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
rtd-denver.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-18 07:16:17 UTC · ↺ Refresh
MX Hostnames
- rtddenver-com0i.mail.protection.outlook.com
MX Priorities
- rtddenver-com0i.mail.protection.outlook.com: 5
A / AAAA Records
- 104.18.3.30 (no PTR)
- 104.18.2.30 (no PTR)
- 2606:4700::6812:21e
- 2606:4700::6812:31e
Mail Server IPs
- 52.101.8.50 ↩ mail-dm6pr09cu00202.inbound.protection.outlook.com
- 52.101.8.52 ↩ mail-ds0pr09cu00104.inbound.protection.outlook.com
- 52.101.9.19 ↩ mail-blapr09cu00103.inbound.protection.outlook.com
- 52.101.11.12 ↩ mail-sa9pr09cu00104.inbound.protection.outlook.com
- 2a01:111:f403:f904:: ↩ mail-dm6pr09cu00200.inbound.protection.outlook.com
- 2a01:111:f403:f90e::1 ↩ mail-sa9pr09cu00101.inbound.protection.outlook.com
- 2a01:111:f403:f900::1 ↩ mail-blapr09cu00101.inbound.protection.outlook.com
- 2a01:111:f403:f904::1 ↩ mail-ds0pr09cu00101.inbound.protection.outlook.com
SOA Record
Raw SOA
candy.ns.cloudflare.com dns.cloudflare.com 2397606455 10000 2400 604800 1800
Primary NS (mname)
candy.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2397606455
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
candy.ns.cloudflare.com
olof.ns.cloudflare.com
SPF Record
✓ Soft Fail (~all)
v=spf1 a include:spf.protection.outlook.com include:_spf.salesforce.com include:service.govdelivery.com include:spf_c.oraclecloud.com ip4:13.108.0.0/14 ip4:208.75.120.0/22 ip4:205.207.104.0/22 ip4:160.34.15.0/24 ip4:65.114.238.134 ip4:72.18.152.155 ip4:216.146.32.161 ip4:216.146.32.188 ip4:216.146.32.187 ip4:216.146.32.186 ip4:216.146.32.185 ip4:81.93.173.201 ip4:81.93.164.103 ip4:159.183.158.11 ip4:149.72.231.47 ip4:149.72.196.66 ~all
📊 DNS lookups: 5/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; pct=100; rua=mailto:[email protected];
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 4 found
selector1._domainkey
selector2._domainkey
s1._domainkey
s2._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
7 records- adobe-idp-site-verification=76eca765f420188d85f66cb5ef8c87108e0949efa0ae1ad5fbad6920ec0111e4
- apple-domain-verification=oyNuE1qOG0E7MoNg
- atlassian-domain-verification=ZdY8/JCd5uDF/6PbvgKuA3Cb4MHlts1iRXzJtYdYDZyAZPhvCd3W5wKCHUpNMQvc
- SPFv=spf1 a include:spf.protection.outlook.com include:_spf.salesforce.com include:service.govdelivery.com include:spf_c.oraclecloud.com ip4:13.108.0.0/14 ip4:208.75.120.0/22 ip4:205.207.104.0/22 ip4:160.34.15.0/24 ip4:65.114.238.134 ip4:72.18.152.155 ip4:216.146.32.161 ip4:216.146.32.188 ip4:216.146.32.187 ip4:216.146.32.186 ip4:216.146.32.185 ip4:81.93.173.201 ip4:81.93.164.103 ip4:159.183.158.11 ip4:149.72.231.47 ip4:149.72.196.66 ~all
- CYYiVzJwqhuw/SHd50oEryhcOy285b6fc7LVD+cu+OaIT+ErzLeXMmnO276h3njrfQASU5EtVcVizKAGWzzZRg==
- MS=ms19639081
- _hmmh5uybng0stjb9qtdgxg4qqdujvww
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