Hi, I've installed the newest ISPConfig (3.1.6) on Debian 9.1. And whatever I'm doing, Let's Encrypt creates certificates only for 'mydomain.com', completly omitting 'www.mydomain.com'. And yes, I have auto subdomain set to 'www'. What may be the problem? :-( EDIT: SOLVED! My server is behind the router, so I had to skip checking by Let's Encrypt.