Domain Overview
DNS: ✓ 1mo ago
Checker: ✓ 1mo ago
castuk.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-04-06 15:36:52 UTC · ↺ Refresh
MX Hostnames
- castuk-com.mail.protection.outlook.com
MX Priorities
- castuk-com.mail.protection.outlook.com: 5
A / AAAA Records
- 46.101.86.172 ↩ castuk.com
Mail Server IPs
- 52.101.68.3 ↩ mail-db7pr03cu00403.inbound.protection.outlook.com
- 52.101.73.12 ↩ mail-am4pr0401cu00104.inbound.protection.outlook.com
- 52.101.73.22 ↩ mail-am7pr05cu00106.inbound.protection.outlook.com
- 52.101.73.153 ↩ mail-as8pr05cu00401.inbound.protection.outlook.com
- 2a01:111:f403:ca09::3 ↩ mail-am6pr04cu00303.inbound.protection.outlook.com
- 2a01:111:f403:ca04:: ↩ mail-db3pr0202cu00100.inbound.protection.outlook.com
- 2a01:111:f403:ca04::b ↩ mail-dbbpr03cu00103.inbound.protection.outlook.com
- 2a01:111:f403:ca09::1 ↩ mail-as9pr07cu00301.inbound.protection.outlook.com
SOA Record
Raw SOA
ns0.zen.co.uk dnsmaster.zen.co.uk 2021041507 2400 3600 2419200 300
Primary NS (mname)
ns0.zen.co.uk
Admin Email (rname)
dnsmaster@zen.co.uk
Serial
2021041507
Refresh
2400s
Retry
3600s
Expire
2419200s
Minimum TTL
300s
Nameservers (NS)
ns0.zen.co.uk
ns1.zen.co.uk
SPF Record
✓ Soft Fail (~all)
v=spf1 ip4:88.98.253.230/32 ip4:109.111.201.240/32 include:spf.protection.outlook.com include:sendgrid.net include:_spf.bullhornmail.com ip4:40.127.192.217 include:sparkpostmail.com ~all
📊 DNS lookups: 4/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; rua=mailto:[email protected]; ruf=mailto:[email protected]; adkim=r; aspf=r; ri=86400; fo=1; rf=afrf; pct=100
✓ 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: 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
5 records- google-site-verification=JqQgG6kK6sfFZE5LulfU9NyWBat33q6UDhRqAuHJRlI
- linkedin-site-verification=292108d0-ac58-4db6-829d-548f44d4e380
- MS=ms38060041
- SPFv=spf1 ip4:88.98.253.230/32 ip4:109.111.201.240/32 include:spf.protection.outlook.com include:sendgrid.net include:_spf.bullhornmail.com ip4:40.127.192.217 include:sparkpostmail.com ~all
- google-site-verification=QRlMQwmZ9ys4XdAkNy4rAqM6ChiLHXDDHTVhUIO9ees
Full email verification for castuk.com
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