Blank Command Errors

Problem

While provisioning an account on a Plesk server using the Plesk module, you see a blank command error.

Cause

This issue can occur if your firewall is blocking connections on port 8443.

Solution

This troubleshooting information only applies to self-hosted WHMCS installations.

Open port 8443 on the WHMCS server and the Plesk hosting server for both inbound and outbound connections.

troubleshooting troubleshooting-article plesk

Last modified: 2025 October 17