- Check your target system. Confirm the operating system and CPU architecture in system settings, then choose the matching package. x64 and arm64 are architectures, not performance tiers; DEB and RPM are package formats, not connection modes. The wrong choice usually prevents installation or startup and can't be fixed by changing server settings.
- Keep your existing settings. If you already use a client, export your servers, subscriptions, custom routes and DNS settings first. Note the local ports and traffic-routing mode. Backups may contain connection credentials, so store them somewhere you control. Don't post an entire configuration folder in a public discussion as a troubleshooting attachment.
- Import a working connection. After installation, import a connection in the client using a subscription URL, a link from your clipboard or a supported configuration file. A subscription name is just a label; it doesn't replace the server address, port, authentication or transport settings. Check that the fields imported correctly.
- Choose a mode and test it. Select a server, then enable the proxy method that fits your needs. The system proxy mainly affects apps that respect system proxy settings; TUN routes more traffic and requires additional permissions and routing checks. Verify the basic connection first, then add split tunneling, DNS and startup settings.
Once you've completed these steps, test the connection with the app you actually need and check the client's logs for error categories. Timeouts, authentication failures and DNS resolution errors require different troubleshooting. Don't reinstall after a single failed test or change the protocol, DNS, routing and proxy mode all at once; keep a baseline you can compare against.