Look in your server's config file for a section that looks like the below:
Code:
<zones>
<defaultstatus>0</defaultstatus>
<!-- Sets port range for world to use to auto configure zones -->
<ports low="7000" high="7500"/>
</zones>
By default, where I have 0, it is normally set to 20 (don't ask me why that is in the default config, because I dunno). Just set that to 0 and then set any accounts in your account table (other than GM accounts) down to 0 as well.