Cobra Forum

Question: Website hosted on Plesk server is not accessible via HTTPS: This site can't be reached


Applicable to:

• Plesk for Linux
• Plesk for Windows

Symptoms

• A website hosted on a Plesk server is not accessible via HTTPS:

Server not found
Could not locate remote server
This page can't be displayed
This site can't be reached

• Web Server's Default Page may be shown instead of the site's content.
• The Let's Encrypt certificate can not be issued for the domain in Domains > example.com > SSL/TLS Certificates with the following error:

Could not issue an SSL/TLS certificate for example.com Details Could not issue a Let's Encrypt SSL/TLS certificate for example.com Details No domains have passed validation

• The website works properly over HTTP or redirects to HTTPS:

# curl -I http://example.com/ -v
* About to connect() to www.example.com port 80 (0)
* Trying 203.0.113.2... connected
.........
< Location: https://example.com/
Location: https://example.com/


Cause

SSL/TLS support option is disabled for the domain but a redirection to HTTPS might have been enabled in the website configuration/code.


Resolution

1.Log in to Plesk.

2.Go to Domains > example.com > Hosting Settings and enable the option SSL/TLS support:

(https://pix.cobrasoft.org/images/2025/12/30/SSL-TLS2.png)