theory.com

Valid Email Server

Domain Overview

DNS: ✓ 2mo ago Checker: ✓ 2mo ago
theory.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]

Checked via [email protected] · 2026-03-21 01:02:33 UTC · ↺ Refresh

MX Hostnames

  • theory-com.mail.protection.outlook.com

MX Priorities

  • theory-com.mail.protection.outlook.com: 5

A / AAAA Records

  • 96.45.83.1 ↩ redirection.dnsmadeeasy.com
  • 96.45.82.42 ↩ redirection.dnsmadeeasy.com
  • 96.45.82.155
  • 96.45.83.150

Mail Server IPs

  • 52.101.157.10 ↩ mail-os0p286cu01302.inbound.protection.outlook.com
  • 52.101.157.11 ↩ mail-os0p286cu01203.inbound.protection.outlook.com
  • 52.101.124.1 ↩ mail-ty3p286cu00101.inbound.protection.outlook.com
  • 52.101.124.5 ↩ mail-tyvp286cu00305.inbound.protection.outlook.com
  • 2a01:111:f403:cc1a::1 ↩ mail-ty3p286cu00101.inbound.protection.outlook.com
  • 2a01:111:f403:cc1a::3 ↩ mail-tyvp286cu00203.inbound.protection.outlook.com
  • 2a01:111:f403:cc1f::1 ↩ mail-os0p286cu01201.inbound.protection.outlook.com
  • 2a01:111:f403:cc24:: ↩ mail-os0p286cu01300.inbound.protection.outlook.com

SOA Record

Raw SOA ns10.digicertdns.com dns.digicertdns.com 2009036460 43200 3600 1209600 180
Primary NS (mname)
ns10.digicertdns.com
Admin Email (rname)
dns@digicertdns.com
Serial
2009036460
Refresh
43200s
Retry
3600s
Expire
1209600s
Minimum TTL
180s

Nameservers (NS)

ns4.dnsmadeeasy.com
ns3.dnsmadeeasy.com
ns2.dnsmadeeasy.com
ns1.dnsmadeeasy.com
ns0.dnsmadeeasy.com

SPF Record

✓ Soft Fail (~all)
v=spf1 include:support.zendesk.com include:mail.zendesk.com include:u1884086.wl.sendgrid.net include:spf.protection.outlook.com include:_spf.salesforce.com a:production.web.theory.demandware.net include:spf.intermedia.net +ip4:210.169.200.224/27 ~all
📊 DNS lookups: 7/10
~ Soft fail (~all) — moderate enforcement

DMARC Record

~ Quarantine
v=DMARC1; p=quarantine; pct=100; rua=mailto:[email protected]
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed · DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]

DKIM Selectors

✓ 6 found
google._domainkey
selector1._domainkey
selector2._domainkey
k1._domainkey
s1._domainkey
s2._domainkey
✓ Public key: 392 chars (valid)
✓ DKIM properly configured for selector: google

Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses

All TXT Records

11 records
  • SPFv=spf1 include:support.zendesk.com include:mail.zendesk.com include:u1884086.wl.sendgrid.net include:spf.protection.outlook.com include:_spf.salesforce.com a:production.web.theory.demandware.net include:spf.intermedia.net +ip4:210.169.200.224/27 ~all
  • apple-domain-verification=XcAY1V8vdF3eN6p7
  • google-site-verification=qk5T2AtYiOfgDECD8hrwgYpHJNAYaVrRuY2wdP7cpfY
  • facebook-domain-verification=22umle1tf4z35l22ot442u9jkw0w5r
  • 998e759d81e34fedb06ffc19411d9d71
  • MS=ms62625959
  • sfcc_verification_aado=1bbb0491a4be902271c01387bbc964220574d28994ac3cd7c150a73989183b24
  • google-site verification=vKHE6qn0qWMfWEDm33vL9d1BxnuuktcoAWJtFwPtMJs
  • atlassian-domain-verification=DWDHXMar9/0VPemzDGa693escrPzjw0dO16bdfX5MMee6HsZ2pi3gu3qVBgl9z32
  • google-site-verification=alNhedMF8_AqGOLHzqDUqwMAoWh008dx5mcNgrn6Rc4
  • hgNjckvrUxFmbKF+tpfDtN1X2FovQCJQcYmV8lPofYNQ3pkV6osFuF9L5Gpthb+ltWClgGUyY+ZD5IwR+kisyg==
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