Connect a domain without disrupting email
Understand nameservers and website records, preserve mail settings and verify the new connection before retiring your old host.
Find where DNS is managed
Domain registration, DNS hosting, website hosting and email may be supplied by different companies. You usually do not need to transfer a domain registration just to move a website. First identify the authoritative nameservers and the account that manages their DNS zone. Editing a zone that is not authoritative will not update the records visitors use.
Record the existing zone before making changes. Keep the record names, types, values, MX priorities and TTL values together. Use your DNS provider export if available. Store that backup privately because verification records can reveal details about your services.
Change only what the website needs
An A record directs a hostname to an IPv4 address; AAAA does the same for IPv6. A CNAME points a name to another name. Use the exact connection details supplied for your hosting, including whether the bare domain and www need different settings. Do not copy an example IP address into your real zone.
Changing authoritative nameservers hands the zone to another DNS service. Prepare all required records there first, not just the website record. Preserve MX and email authentication records, verification TXT records and any other working services. If DNSSEC is enabled, coordinate the signing and parent DS records with the DNS providers before changing delegation.
Check the website and email separately
DNS caches retain observations according to their TTL. Different networks may see different answers during a change. Check the exact hostname that fails rather than repeatedly changing records. A DNS lookup is a useful observation, not proof that every network has refreshed.
Open both the bare domain and www over HTTPS. Check important pages, redirects and forms. Test inbound and outbound email with an address you control; loading a website does not establish that mail is working. Keep the old service available while you investigate inconsistent results.
HostMixo DNS lookup reads public records without editing them. For an owned service, My Services provides its available connection details and management actions. If you need help, include the hostname, change time and observed error in a support ticket, but never send account passwords or domain transfer codes.