When a VPN connection won't start, the cause is usually local: credentials, an outdated configuration, a firewall or the system clock. This guide runs a diagnosis in order, from the simplest to the most technical, before you open a ticket.
1. Check the subscription and the credentials
Open your client area and check the subscription status: a period that has ended or a pending payment can prevent access to the tunnel. Then check the username and password, avoiding spaces added by automatic copy and respecting capital letters.
2. Check the imported configuration
Reload the configuration from the client area if the tunnel fails after a change of device or network. Each configuration is tied to one device: a key installed on another machine may be rejected. Never edit the file you received; re-import it instead, and make sure the QR code was scanned in full.
3. Firewall, antivirus and network
A local firewall, an antivirus with a network module or a corporate network can block the ports needed to bring the tunnel up. Test from another network: a mobile hotspot or another Wi-Fi. If the connection works on mobile but not in the office, the filtering comes from the corporate network.
4. Check for DNS leaks
After connecting, if pages load slowly or return resolution errors, check DNS leaks: compare the public IP address and DNS server reported by a test tool with those expected from the VPN. A local DNS still in use often explains traffic that bypasses the tunnel.
5. Update or reinstall the client
Update the client and the operating system, restart the device and try again. On Windows, check that the client service is running; on macOS, allow the client in the security and privacy settings. Turn off any other active VPN client: two tunnels at once conflict.
6. Collect the information for support
- The exact error message and, if available, the client log.
- The operating system and its version, plus the application version.
- The type of network in use: home, office or mobile hotspot.
- The date and time of the attempt.
- The name of the configuration involved, never the private key or the full file.
With these details, support can reproduce the problem and guide you; without them, back-and-forth messages lengthen the resolution.
