Proton Mail
Useful for encrypted email, custom-domain mail, email aliases, and privacy-focused business communication.
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DNS & Domain Health Checker
Check your domain, DNS records, website status, SSL certificate, email setup, SPF, DMARC, and common configuration issues in one place.
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Domain Health Summary
Health report
Enter a public domain to check DNS, website status, SSL, email DNS, redirects, and common configuration issues.
Port233 Toolkit
Managing DNS, domains, or email setup?
Use the Cyber Essentials resource and IT Consultant Bundle Pack to document DNS records, domain ownership, email security, SPF/DKIM/DMARC checks, renewals, and client handover notes.
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If your DNS or domain setup needs fixing, you may need a reliable domain registrar, DNS provider, email host, or privacy-focused business suite.
Proton for Business
Useful for privacy-focused business email, VPN, password management, secure storage, and team controls.
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DNS, email, SSL, and domain health basics
What is DNS?
DNS connects a domain name, such as example.com, to the servers and services that run the website, email, and other internet services for that domain.
What are A and AAAA records?
A records point a domain to an IPv4 address. AAAA records point a domain to an IPv6 address. These records help browsers find the server hosting your website.
What are MX records?
MX records tell other mail servers where to deliver email for your domain. If a domain has no MX records, it may not be able to receive email.
What is an SPF record?
SPF is an email security record that lists which servers are allowed to send email for your domain. It helps reduce spoofing and fake email.
What is a DMARC record?
DMARC tells receiving mail servers what to do when an email fails SPF or DKIM checks. It can be used to monitor, quarantine, or reject suspicious email.
What is DKIM?
DKIM adds a digital signature to outgoing email. It helps receiving mail servers verify that the email was genuinely sent by an authorised system and was not changed in transit.
What is an SSL certificate?
An SSL certificate allows a website to use HTTPS. It helps encrypt traffic between the visitor and the website and proves that the certificate was issued for the domain.
Why does HTTP to HTTPS redirect matter?
If HTTP does not redirect to HTTPS, visitors may access an insecure version of the website. Redirecting to HTTPS helps protect users and improves trust.
What is a domain health check?
A domain health check reviews the main technical settings that keep a domain, website, and email working properly. This includes DNS, SSL, redirects, and email security records.
Need help fixing your domain, website, or business email?
Port233 helps small businesses configure DNS, websites, SSL certificates, Microsoft 365, Google Workspace, email security records, and reliable online infrastructure.