open_basedir restriction proper plugin settings | Peter's Custom Anti-Spam for WordPress | Forum

In this section:

// Leave this as FALSE unless you have an open_basedir restriction on your server and can't get it removed. In that case, enter the server path to your blog (different from the site address!) like in the example below WITH a trailing slash.
// $cas_abspath = "/home/yourusername/public_html/blog/";
$cas_abspath = false;

The first cas_abspath line is an example that does not factor into the plugin. If you are going to enter the server path, it should look something like this:

// $cas_abspath = You can write anything on this line. It is the line below that matters.
$cas_abspath = "/home/peter/public_html/wordpress/";

In other words, DO NOT do something like this:
// $cas_abspath = "/home/peter/public_html/wordpress/";
$cas_abspath = true;

Did you use proper quotes? "/path/"

You could also try using single quotes: '/path'

If neither of those work, is the word "default" in your path for some reason?

If all of the above fails, e-mail me the plugin file (contact info on the right sidebar on theblog.ca).

Of course, if your plugin is working and it's only the diagnostic page that gives the error, there's no need to fix it, I suppose…