When a row won't start, a source won't appear, a permission is missing, or your Orbit viewers can't watch, the fix is almost always one specific control. This page maps the symptom to the setting that resolves it.

Gut-check first: if a stream "works on another machine but not this one," suspect a VPN or kill-switch (e.g. NordVPN) or macOS Local Network privacy before anything else. These silently block both local NDI discovery and SRT. See Rule out a VPN / kill-switch.

Opening the Dependencies window

This window shows whether the NDI Runtime and GStreamer (needed for SRT) are installed, and on Windows it adds a firewall section.

1. Click the version string in the header to open About.
2. Click "System Dependencies & Firewall".

On Windows, this window also auto-opens a second or so after launch if a dependency or firewall issue is detected.

"No Sources" on launch

This is the normal empty state, not an error.

1. Click "Set up a source" on the No Sources card (or the footer + once rows exist).
2. Pick a source type in the Select Source Type modal.
3. Tip: pick GEN (test card) to verify an output path end-to-end with no camera or network source. See Screen / Camera / Test Card sources.

START did nothing / a row was skipped

Pulsar starts what it can and skips anything that isn't fully configured, so the rest of the batch still goes.

1. Watch for the toast: "Skipped N unstartable outputs (missing URL/source/camera): …" — easy to miss.
2. SRT caller output: open the output settings and enter a valid srt://host:port URL. See Outputs (SRT / NDI).
3. SRT source row: open the SRT input modal and configure a Caller URL or a Listener port. See SRT input source.