For gTLD domain names (i.e. those ending in .com, .net and .org), the most common problem in delegating domain names is that one or more of the Name Servers to which you are delegating is not registered with the NSI Registry. NSI is the former monopoly issuer of all gTLD names; some time ago this registry system was opened up to competition but NSI still maintains some core aspects of the gTLD system. (NSI is also known as VeriSign Global Registry Services or VeriSign GRS).|
The error message you will typically receive if your nameservers are not registered withh NSI is as follows:
"NameServer 1 is not a valid NameServer"
A simple means of verifying that a name server is registered is to go to VeriSign's Whois Server and carry out a search. You need to type your nameserver in the box (e.g. "NS1.EXAMPLE.COM") and then make sure the "Nameserver" radio button is selected (rather than domain name or registrar whois search).
If there is no entry for the name-server that you have specified then it is not registered and therefore cannot host generic top-level domains (gTLDs).
Normally, only an ISP or hosting company will need to register a nameserver, so if you are a seeing this error and someone else is providing your hosting service, you should contact them for help.
If you are registering your own new nameservers, you need to contact the registrar who is responsible for management of the parent domain name under which you wish to establish nameservers. For example, to register NS1.EXAMPLE.COM you need to contact the registrar for EXAMPLE.COM and follow their procedures for new nameserver registration. (You can do a registrar search via www.crsnic.net if you are not sure who your registrar is for a particular domain name.)
If you wish to register a new nameserver using a ccTLD nameserver (i.e. register a nameserver such as NS1.EXAMPLE.CO.UK or NS1.EXAMPLE.COM.AU so that it can host gTLD names) this can be done through any gTLD registrar. Generally the information required in this case will be the fully qualified host name and IP address as well as your authority to request registration of the name server.