VPN – Troubleshooting Guide
EN
This guide helps you to fix the most common issues related to VPN. Please follow the steps below before contacting support.
1. Types of Problems
Problems related to VPN can appear in different ways.
🌐 Connection Issues
❌ Unable to start VPN connection
🔑 Authentication error (invalid credentials)
⚠️ Connection fails or does not start
🔓 Post-Connection Issues
🌐❌ VPN connects, but no access to internal resources
🔁 Unstable connection or frequent disconnections
🚀 Performance Issues
🐌 Slow connection
⚠️ Internal applications not responding
⏱️ Delays or communication failures
2. Checks to Perform
Checks should be carried out in the order indicated, testing the service after each step.
Before You Start
- Does the issue occur on only one device or multiple devices?
- Does the error occur consistently or occasionally?
- Did it start after any change (network, location, device)?
Check Internet Connection
- Open a website (e.g., google.com)
- Test more than one website
Expected result: You can browse the internet without issues
Validate Access Credentials
- Confirm your Iscte username and password
- Check that your account is not locked
- Test access to other services:
Check VPN Application
- Confirm the VPN application is properly installed
- Update to the latest version (see: VPN Setup)
Restart Equipment
- Restart your device
- Restart your router (if applicable)
Verify VPN Settings
- Check VPN server address: vpn.iscte-iul.pt
- Confirm the protocol in use (if applicable)
Check Security Interference
- Ensure firewall or antivirus is not blocking the VPN
- Temporarily disable for testing only (re-enable afterward)
Test on Another Network
- Connect to the VPN using a different network (e.g., mobile hotspot)
Verify Access to Internal Resources
3. Best Practices
The following best practices aim to ensure efficient, secure, and continuous use of the services. Applying them helps prevent issues, improve performance, and simplify troubleshooting when problems occur.
Network
- Use a stable connection (prefer a wired connection whenever possible)
- Avoid unsecured public networks
- Ensure strong Wi‑Fi signal strength
Usage
- Use only the GlobalProtect VPN client
- Protect your access credentials
- Disconnect the VPN when not in use
Performance
- Close unnecessary applications while connected
- Monitor connection quality
- Regularly update software and operating system
3. User Support
If the issue persists after completing all checks, you should contact IT Support.
Quick Checklist
Before contacting Support, confirm:
- 🌐 Internet funcional (consegue abrir vários sites)
- 🔑 Credenciais corretas (consegue aceder a outros serviços)
- 🔄 Aplicação VPN atualizada
- 🔁 Equipamento reiniciado
- 🔁 Firewall e Anti-vírus não estão a bloquear a ligação
- 📶 Teste realizado noutra rede (ex: hotspot móvel)
Information to Provide
To ensure faster and more effective analysis, always include the following information in your request:
Context
- Location (e.g., Iscte, home, public network)
- Date and Time (When the issue occurred)
- Type of device (computer, smartphone, etc.)
- Type of Problem (e.g., unable to start VPN connection, VPN connects, but no access to internal resources, etc.)
Problem Details
- Detailed description of the problem
- When the issue started
- Whether it affects other users
- Whether it occurred after any change
Tests Performed
- List of troubleshooting steps already performed
Evidence
- Screenshots
- Error messages
- Observed behavior
Support Channels
Example Requests
Example 1
I am trying to connect to Iscte’s VPN from home, but the connection fails with a “Connection Timeout” error message.
The problem has occurred since today (22/05/2026) and prevents access to the internal systems.
I have already carried out the following checks:
- Confirmed that the Internet connection is working
- Restarted the computer and the router
- Updated the VPN application
- Temporarily disabled antivirus/firewall for testing
- Tested connection via mobile hotspot (same problem)
The situation persists, so I would appreciate it if the service or the configuration associated with my account could be checked.
Example 2
I am able to successfully connect to the ISCTE VPN from home; however, I cannot access internal resources (e.g., network folders and institutional applications).
The issue has been occurring since 05/21/2026 and persists across different sessions.
I have already performed the following tests:
– Disconnected and reconnected the VPN
– Restarted the computer
– Tested different internal applications (all inaccessible)
– Confirmed that the Internet is functional
The VPN connection shows as active (“Connected”), but there is no functional access to the services.
I kindly request verification of the permissions or VPN configuration associated with my account.