I found the /usr/sbin/in.named file but it is encoded.
I tried the /usr/sbin/ndc rstart command to start the DNS server but it didn't work. Are there any other commands to start the DNS server beside the one I tried?
What version of Unix are you using?
he is using Solaris 8 for intel.
The named process will not start if the configuration file (named.boot or named.conf) is not set up properly. You might consider purchasing the OReilly book on DNS and Bind and do a lot of homework about how to setup DNS. This will save you lots of time and frustration 
that book is a great place to start. Another fine book from the boys and girls @ oreilly.
I would also check your syslog for daemon errors. this will start pointing out problems w/ and daemons.