Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
nucleus-cf.co.uk
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-20 18:38:40 UTC · ↺ Refresh
MX Hostnames
- nucleuscf-co-uk01i.mail.protection.outlook.com
MX Priorities
- nucleuscf-co-uk01i.mail.protection.outlook.com: 10
A / AAAA Records
- 4.231.170.49 (no PTR)
Mail Server IPs
- 52.101.68.15 ↩ mail-db6pr03cu00107.inbound.protection.outlook.com
- 52.101.73.30 ↩ mail-am7pr05cu00306.inbound.protection.outlook.com
- 52.101.68.39 ↩ mail-db7pr03cu00607.inbound.protection.outlook.com
- 52.101.73.153 ↩ mail-as8pr05cu00401.inbound.protection.outlook.com
- 2a01:111:f403:ca04::d ↩ mail-db6pr03cu00105.inbound.protection.outlook.com
- 2a01:111:f403:ca09::6 ↩ mail-am4pr0401cu00106.inbound.protection.outlook.com
- 2a01:111:f403:ca04::8 ↩ mail-db5pr02cu00100.inbound.protection.outlook.com
- 2a01:111:f403:ca09::c ↩ mail-as8pr05cu00304.inbound.protection.outlook.com
SOA Record
Raw SOA
ns0.zen.co.uk netman.zen.co.uk 2025011534 14400 1800 604800 86400
Primary NS (mname)
ns0.zen.co.uk
Admin Email (rname)
netman@zen.co.uk
Serial
2025011534
Refresh
14400s
Retry
1800s
Expire
604800s
Minimum TTL
86400s
Nameservers (NS)
ns0.zen.co.uk
ns1.zen.co.uk
SPF Record
✓ Soft Fail (~all)
v=spf1 include:spf.protection.outlook.com include:_spf.salesforce.com include:transmail.net.in include:spf.uk.exclaimer.net include:mail.zendesk.com include:email.cloud4j.com ~all
📊 DNS lookups: 6/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine; pct=100
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)
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
4 records- 78mcbpb5mv5kjobo6c4r1uj19k
- zoho-verification=zb97086921.zmverify.zoho.in
- SPFv=spf1 include:spf.protection.outlook.com include:_spf.salesforce.com include:transmail.net.in include:spf.uk.exclaimer.net include:mail.zendesk.com include:email.cloud4j.com ~all
- apple-domain-verification=yPfUurTDClH8DLas
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