e questi tentativi?

codice:
- localhost cannot be resolved or resolved incorrectly, make sure that localhost entry exists in /etc/hosts.
 
127.0.0.1 localhost localhost.localdomain
 
- if you see connection refused error, try to start Plesk and make sure that there is no firewall running on the server that blocks 8443 port.
 
- also check that Plesk is configured to run on the 8443 port, Listen 8443 directive must be in the $PRODUCT_ROOT_D/admin/conf/httpsd.conf.
 
- check that you are able to login to Plesk CP in usual way via browser.

- finally make sure that Plesk is responding on DrWEB request by running the following command on the Plesk server, it should be:

# curl -d "challenge=123&checker=drweb" https://localhost:8443/check-plesk.php -k
response=%7BS%D0%18%A5%F1%CF6Z%13%26%.....