How ASP is config ie:cdonts not workng

I’m looking for information on the relationship between the cdonts mail object and the ASP config on a web server. I’ve been challenged to find out the proper config and to provide research materials from a proven best practices point of view. Theexchange 2k environment is new to me and advanced web server configs are also new to me, nonetheless I can’t help but think this is a smtp issue of connectivity. Anyone familiar with why access is intermittent?