Prepare the installer and subscription separately
The installer provides the client; the subscription provides configuration data the client can load. The program alone usually can’t connect without a usable configuration. Make sure you’re authorized to use the subscription and that its format is supported. Subscription URLs may contain access credentials, so keep them private.
If importing a configuration reports missing fields or an unsupported protocol, first check its format and the core’s capabilities. Renaming the file won’t fix the problem; different configuration formats aren’t necessarily compatible.
Keep local changes before updating in place
Before updating, note your subscription source, export the configuration if possible, and save any local overrides, DNS settings, and proxy group selections. Client updates and subscription updates are separate: refreshing a subscription may regenerate remote configuration and replace edits made directly to the subscription file.
When switching clients, it’s safer to import your configuration again. Don’t copy the entire old application data directory into the new one; file layouts, cache formats, and permission records may differ.
Test the connection before enabling background operation
After installation, launch the client manually and check that the configuration loads, the right proxy is selected, and connection permissions are granted. Only then enable startup or background operation on your phone, so unresolved configuration issues don’t carry over into automatic startup.
If the connection fails, identify whether the problem is with downloading, installation, configuration loading, or network routing. A specific error message is more useful than repeated reinstalls. Before asking for help publicly, redact subscription URLs and other private configuration details.