Rmdir
From Scriptwiki
Removes the specified directory.
/rmdir <directory>
If there are spaces in the directoryname, you need to use double quotes. The directory cannot be deleted if it contains files. If no special path is given mIRC assumes to find the file using the mIRC directory as basedir.
Example
Removes the directory "downloads"
/rmdir downloads
Removes the directory "my files"
/rmdir "my files"
See Also
To delete files: /remove