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VPN won’t start

If the VPN fails to start, check these common causes:
SlipStream GUI requires ports 8080 (HTTP proxy) and 5201 (SOCKS5) to be available.Check if ports are in use:
macOS/Linux
lsof -i :8080
lsof -i :5201
Windows
netstat -ano | findstr :8080
netstat -ano | findstr :5201
Kill processes using the ports:
macOS/Linux
lsof -ti:8080 | xargs kill -9
lsof -ti:5201 | xargs kill -9
Windows (Admin)
# Find PID from netstat output above, then:
taskkill /PID <PID> /F
The app will automatically attempt to kill the process on port 5201 if it detects “Address already in use” errors.
The SlipStream client binary might be missing or quarantined.Expected locations:
  • macOS: binaries/slipstream-client-mac-arm64 or slipstream-client-mac-intel
  • Windows: binaries/slipstream-client-win.exe
  • Linux: binaries/slipstream-client-linux
Solutions:
  • Reinstall the application from the latest release
  • Check if antivirus quarantined the binary (especially on Windows)
  • Ensure the binary has execute permissions (macOS/Linux)
Verify your configuration settings:
  • DNS Resolver: Must be in format IP:PORT (e.g., 8.8.8.8:53)
  • Domain: Your SlipStream server domain (e.g., s.example.com)
Test your DNS resolver:
  1. Click “DNS Checker” in the app
  2. Enter a test domain (e.g., google.com)
  3. Test your DNS servers
  4. Click “Use” on any OK result to apply it

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System proxy not working

The HTTP proxy runs on 127.0.0.1:8080 regardless of system proxy configuration.Manual configuration:
  • Proxy address: 127.0.0.1
  • Port: 8080
  • Bypass: Add local addresses if needed
Platform-specific requirements:
  • macOS: May prompt for administrator password
  • Windows: Run as Administrator for automatic configuration
  • Linux: System proxy works with GNOME (gsettings); other DEs may need manual setup
Not all applications respect system proxy settings.Solutions:
  • Configure individual apps to use proxy 127.0.0.1:8080
  • Use the Proxy Bypass List to exclude specific domains/IPs
  • Some apps (like terminal tools) need environment variables: 
    export http_proxy=http://127.0.0.1:8080
export https_proxy=http://127.0.0.1:8080
If system proxy remains configured after stopping:macOS:
networksetup -setwebproxystate "Wi-Fi" off
networksetup -setsecurewebproxystate "Wi-Fi" off
Windows (Admin):
netsh winhttp reset proxy
Linux (GNOME):
gsettings set org.gnome.system.proxy mode 'none'

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Connection issues

Use the built-in connection tester to diagnose issues.Common errors:
ErrorSolution
Connection refusedVPN not running - click “Start VPN”
TimeoutCheck DNS resolver and domain settings
HTTP 500SOCKS5 connection failed - check SlipStream server
Invalid responseProxy or server misconfiguration
Manual test:
curl -x http://127.0.0.1:8080 http://httpbin.org/ip
If you see “Path for resolver became unavailable” or “Connection closed, reconnecting”:
These messages are normal during reconnection attempts and appear as logs, not errors.
To fix persistent DNS issues:
  1. Use the DNS Checker to test multiple DNS servers
  2. Select a working DNS server and click “Use”
  3. Common reliable DNS servers:
    • Google: 8.8.8.8:53
    • Cloudflare: 1.1.1.1:53
    • Quad9: 9.9.9.9:53
Check the Logs panel for specific errors:
  • ECONNRESET / EPIPE / ETIMEDOUT: Normal socket errors under load, app will continue
  • Address already in use: Port conflict (see “Ports already in use” above)
  • SlipStream process exited: Check server configuration and connectivity

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Enable verbose logging

Verbose logging shows detailed connection information for debugging:
  1. Toggle “Verbose Logging” in the app interface
  2. Restart the VPN to capture full startup logs
  3. Check the Logs panel for detailed output
What verbose logging shows:
  • Individual HTTP/HTTPS requests with request IDs
  • SOCKS5 connection establishment
  • Tunnel creation and lifecycle events
  • Socket operations and closures
Verbose logging can be very noisy. Disable it for normal use to reduce log clutter.

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Testing your connection

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Built-in test

  1. Click “Test Proxy Connection” in the app
  2. Wait for the result (tests httpbin.org/ip)
  3. Success shows your exit IP and response time

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Manual testing

Test HTTP proxy: 
curl -x http://127.0.0.1:8080 http://httpbin.org/ip
Test HTTPS: 
curl -x http://127.0.0.1:8080 https://httpbin.org/ip
Check your exit IP: 
curl -x http://127.0.0.1:8080 https://api.ipify.org
Test with browser:
  1. Configure browser to use proxy 127.0.0.1:8080
  2. Visit https://www.whatismyip.com
  3. Verify the IP matches your SlipStream server location

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Logs showing errors

Normal messages (not errors):
  • Path for resolver ... became unavailable - Temporary connection loss, will reconnect
  • Connection closed, reconnecting - Normal reconnection process
  • Socket errors (ECONNRESET, EPIPE, ETIMEDOUT) - Expected under load
Actual errors requiring action:
  • Address already in use - Port conflict, kill conflicting process
  • SlipStream client binary not found - Missing or quarantined binary
  • SlipStream failed to start: ENOENT - Binary not found or not executable
  • HTTP 500 - Server error, check SlipStream server configuration
Each request is tagged with a unique ID for tracking:
[1735891234567-abc123] 🔒 CONNECT example.com:443 (HTTPS)
[1735891234567-abc123] ✅ SOCKS5 connected to example.com:443
[1735891234567-abc123] 🔗 Tunnel active: example.com:443
Use the request ID to trace a specific connection from start to finish.

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Need more help?

If these solutions don’t resolve your issue:
  1. Check platform-specific troubleshooting:
  2. Review the GitHub Issues for similar problems
  3. Open a new issue with:
    • Your platform and version
    • Error messages from logs
    • Steps to reproduce the issue

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