The most frequent support question a reseller receives, and the easiest to prevent.
PREPARE A STANDARD MESSAGE
Write one short document with the nameservers you want clients to use, step-by-step instructions for the common registrars, and a note that propagation takes up to 24 hours. Send it with every new account.
IF YOU USE PRIVATE NAMESERVERS
Give clients ns1.yourbrand.com and ns2.yourbrand.com. Verify they resolve to your server IP before you send them to anyone.
IF YOU USE OURS
Give the exact pair for the server your reseller account sits on, either ns3 and ns4 or ns10 and ns11.zillionkinghost.com. Do not guess, and do not reuse a pair from an older account; check your welcome email or the Client Area.
WHAT CLIENTS GET WRONG
Adding your nameservers alongside the old host's instead of replacing them Editing A records instead of nameservers Changing them at the wrong registrar, where a domain was bought through a reseller of a reseller Expecting instant results and changing them back an hour later
Tell them explicitly to replace, not add, and to wait a full day before concluding anything is wrong.
