Hi Igor,
thank you very much for your answer. The nmap und dig tests were successful. In the article you referred to it says that it could also be a 30x redirection. In fact, I have such a redirection. So I removed it, tried to renew the certificate and it worked!!
I thought this was strange...
Hi there,
I am using Plesk Onyx on an Ubuntu Linux to manage a couple of web sites. For most of the domains I use the Plesk "Let's encrypt" extension to manage SSL certificates. This used to work fine until recently when I received an error message that a certificate could not be renewed. I...