!greet isn't a mIRC command. It is something from a script. If your channel has a script running that allows users to type !greet, then the script may only allow you to use it if you're an op or a voice or a specific user. You'd have to talk to whoever runs the script.
If you meant that you want a script to do it yourself, you should really provide details about what !greet is supposed to do. Here is a simple example of what might be a !greet script that may be similar to what you want...
on *:input:*: {
if ($1 == !greet) {
if ($2 == $null || $2 !ison $chan) { echo -a You need to specify a nick who is in the channel you're typing this command in. | return }
.notice $2 Welcome to the channel.
}
}
For this, you include it in Alt-R > File > New. Then, you type !greet
nick and it will notice the message to the nick that you specified (the red text). This only works for you.
If you wanted something else, please provide details of exactly what you want. We don't read minds here.
