Code:
  if ($readn == 0) 
  {

The opening brace '{' can't begin a line. This was causing the script to fail.


You don't need '/' inside of scripts, you can have them if you like, but they are not needed.

Corrected script.
Code:
on ^*:JOIN:#mychannel:{
  var %person = $read(people.ini)
  if ($readn == 0) {
    notice $nick Good day! 
    write people.ini $nick
  }
}


irc.swiftirc.net #msl (mIRC Scripting Language)