The the following message is thrown while accessing Plesk or webmail:
Your connection is not private
This Connection is Untrusted
(Error code: sec_error_unknown_issuer)
In Internet Explorer:
There is a problem with this website’s security certificate.
- In Opera
Opera cannot verify the identity of the server "XXXX", due to a
problem. The server could be trying to trick you
By default, Plesk is using self-signed certificate that does not have a signature from trust center.
1. Purchase an SSL certificate signed for IP address/hostname/domain by a trusted center (Certificate Authority) or install Let's Encrypt extension and obtain a free certificate. See Administrator's Guide - Getting SSL Certificates for details.
2. Add the SSL certificate to Plesk:
Plesk > Tools & Settings > SSL Certificates > Secure Plesk
3. For securing webmail with a certificate, follow the steps from article How to install SSL certificate on webmail in Plesk Onyx
Add the IP address/hostname/domain to exception list of web browser.
For Google Chrome:
- Click the Chrome Menu icon on the far right of the Address bar.
- Click on Settings, scroll to the bottom and click the Show Advanced Settings link.
- Click on Change proxy settings (under Network)
- Click the Security tab > Trusted Sites icon, then click Sites.
- Enter the URL of your Trusted Site, then click Add.
- Click Close > OK.
For Internet Explorer:
- Open Internet Explorer by clicking the Start button .
- In the search box, type Internet Explorer, and then, in the list of results, click Internet Explorer.
- Click the Tools button, and then click Internet options.
- Click the Security tab.
- Now click on Trusted sites and then click on the sites button.
- Enter the Website URL and click on Add.
- Add the site URL, click on Close.
For Opera, the instructions are available here.