I am installing a script and I read in its setup guide that I must chmod some files. How can I do that?
Chmod-ing is not related to the web server. It is rather related to your operating system. On Windows, there is no support for chmod. You can only set a file to be read-only or writable. So in the general case, do not worry about chmod-ing files on Windows, ignore these instructions and your scripts will run with no problems. On Linux, FreeBSD, and MacOS X, you should use the chmod system command. For more information, open a terminal window or a shell, type man chmod, and press the Return key to learn how to use this command.