Uninstall the app, restart your computer, and perform a clean reinstall.

Stick to one primary email for all VPN activities to avoid confusion between trial accounts and paid subscriptions.

This guide provides the definitive steps to resolve login failures and get your CyberGhost VPN back up and running. 1. Common Causes of Login Failures

When you first signed up for CyberGhost, you were likely given a PUK.

This ID proves you own the account.

CyberGhost VPN Login ID and Password Fixed: A Complete Troubleshooting Guide

Before diving into the fixes, it helps to understand why the "Invalid Credentials" error appears: Passwords are case-sensitive.