I don't see the problem that you are referring to. Try going to
http://www.20ishparents.com and let me know if you get the error that you are referring to. I checked it from several different computers that had never visited their forums yet, and the message still displayed properly for me.
Charon -- you enter that into the .shtml page where you want it to display how many visitors & guests are online. Mine is in my header file.