Get a subscription or shared link
Make sure the link comes from a service you're authorized to use. Subscription URLs and individual shared configuration links are different. The client doesn't include a working remote server. A full subscription URL may contain credentials, so store it separately from ordinary web bookmarks.
Import and update the configuration
Add the URL under subscription groups, save it, then update the subscription. Saving the URL alone doesn't retrieve the configuration. Check the server list after the update. If it's empty, review the update result and link format before changing ports or reinstalling the client.
Choose a server and proxy mode
Select a server, then set the system proxy on desktop or the connection mode on Android. Test access using one traffic-routing method before adjusting routing rules. If you need TUN, check the permissions and DNS requirements separately. Turning on a setting doesn't prove the connection works.
Understand the client, core, and server configuration
v2rayN, v2rayNG, and v2flyNG are graphical clients that organize subscriptions, routing, and connection options. Project V is the starting point for the related technology ecosystem; V2Fly and Xray are common core implementations. Similar client names don't guarantee identical protocol, transport, or extension support. If importing a configuration fails, check its required features against the client's capabilities rather than comparing app names alone.
Open source describes the code and its license; free to use describes the cost of the client itself. Whether a remote service charges a fee, how many devices it allows, and when a subscription expires depend on that service's terms. Updating the client generally won't change your subscription status or fix an invalid remote configuration. Distinguish app, configuration, and network issues before troubleshooting to avoid unnecessary reinstalls.
Change one setting at a time during initial testing
Keep the default routing and DNS settings at first. Choose a known working server and test basic access. If something goes wrong, note the server, routing mode, and relevant log details. Remove subscription URLs, credentials, and personal network information before sharing. Change one setting at a time to identify what affects the result.
After confirming the basic connection, add features such as per-app proxying, domain-based routing, or TUN one at a time. The system proxy doesn't force every app to use the same settings, and TUN doesn't guarantee that every protocol and app will work on every network. For menu locations and step-by-step instructions, see the user guide. For platform permissions, traffic routing, and common errors, see the complete documentation.