To your courier problem, please enable debugging in ispconfig and then run the script:
s root on the shell after you created a autoresponder.
Also when i'm adding subdomain folder isn't autocreated.
You mean subdomains in the site modulke? Sunbdomains dont have their own directory, they are aliases of the website where you added them. If you want to have a subdomain with a separate directory, then add a nwe website and enter "sub.domain.tld" in the domain field.