Stream won't start

If your iPhone connects but the picture never arrives — or the connection won't complete — it's almost always one of these. Work through them in order.

Allow it through the firewall

A firewall on your computer can silently block the video before it reaches your phone. Make sure your Adobe app and the PreviewMonitor plugin are allowed through the firewall on your local (private) network.

• Windows: when Windows Defender Firewall first prompts to allow the app, choose Allow access for private networks. If you dismissed that prompt earlier, re-allow the Adobe app in Windows Firewall settings.
• The connection is local-only, so you only need to allow it on your private/home network — not public.

Keep background output enabled (Premiere)

In Premiere Pro's Settings → Playback, make sure "Disable video output when in the background" stays unchecked. If it's ticked, the stream freezes the moment Premiere isn't the front window — which looks exactly like the stream failing to start.

Make sure a sequence or composition is open

The plugin only produces a picture once there's something to play. Open a sequence (Premiere) or composition (After Effects) and drop a clip into the timeline. A connected stream with nothing playing shows a "waiting for video" state rather than a picture.

Restart the Adobe app after installing

If you installed or updated the plugin while Premiere Pro or After Effects was open, quit and relaunch the app so the plugin loads. Until you restart, the device may not appear or may not stream. See Install & enable the plugin.

Confirm the device is enabled

Double-check the plugin is actually switched on:

• Premiere Pro: Settings → Playback — tick PreviewMonitor's Video Stream (and Audio Stream for sound). It appears as PremiereLive.
• After Effects: Settings → Video Preview — turn on Mercury Transmit and tick PreviewMonitor as the device.