Fix Plesk cPanel "Site Can't Be Reached" Error possibly caused by Firewall

Job ID: 38251138

Budget: $25 – $50 USD

I am encountering a "Site can't be reached" error while trying to access my Plesk cPanel site. Having read on plesk, they said Ports 80 or/and 443 may be blocked by a firewall. So need to Open the web ports 80 and 443 on the firewall and unblock them.
Related categories: PHP System Admin Linux Plesk Firewall