Why it matters
MX records decide where email goes. If a buyer takes over a domain and the MX records are wrong, mail can bounce or go to the old owner. For a domain sale, the seller should say whether the name carries live email, and the buyer should set new MX records on the day of transfer. For example, a company moving to Google Workspace enters Google's mail servers as its MX records. Common mistake: moving DNS to a new host and not copying the MX records, which stops all email.
Source: cloudflare.com
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