Can't Build In-Camera VFX Project

I’m trying to build the In-Camera VFX example project but it seems to be failing and this is the redline error in the build log:

UATHelper: Packaging (Windows (64-bit)): LogInit: Display: LogHttpListener: Error: HttpListener unable to bind to
UATHelper: Packaging (Windows (64-bit)): LogInit: Display: LogRemoteControl: Error: Web Remote Call WebSocket server couldn't be started on port 30020

Any suggestions?

Regarding your question, I also encountered the same problem. How did you solve it in the end?

did you solve it

I’m running into this, too.

My Windows Defender Firewall already had rules for UE exceptions, including one for the Web Remote Control module. I deleted all of these, restarted the UE5 editor, and got several prompts for “Allow access?” from the firewall. Did that. Rules for UE Editor are recreated, but none for the Web Remote Control. No change, same error.

Tried manually adding inbound rules allowing 30010 and 30020. Same error.

Tried disabling firewall completely. Same error.

So as much as this looks like a conflict with the firewall, it doesn’t appear to be so.

I’m on Windows 11, UE5 early access 2.

Update: I found a workaround.


  1. Open the Output Log (Window → Output Log in the top menu)
  2. Stop both the servers by entering these commands:

You’ll see each command appear in green in the output log as you enter it. In my case, StopServer reported that the service was stopping; StopWebSocketServer ran without any output. Both commands were necessary to avoid “cannot bind to port” errors.

Repeat this each time you open the editor. It doesn’t seem to be necessary one build to the next.

– Edit –

This lets me get through the packaging process, but the packaged app displays all black. Checking the logs, I see the same error, “unable to bind to port.”

For comparison, I created a new project from the “Game → Blank” template, and this one doesn’t encounter the error during cooking, packaging, or running the packaged game. My “broken” project is based on a video production template – I suspect the issue is around ndisplays, but I only think that because it’s what I’m trying to learn right now :slight_smile:

– More edit! The whole story as it develops! –

In my original project – the production template where I’m trying to use ndisplays – I went into Project Settings → Plugins → Web Remote Control and disabled “Auto Start” for both Web Server and Web Socket Server. Then, I did my above workaround to get through the packaging phase.

The good news: the packaged app runs and shows the scene! No more black view when launched standalone. When launched through NDisplayLauncher, the “cannot bind to port” error no longer appears. Progress!

The bad news: Launched through NDisplayLauncher, the app still shows a black screen.

In the logs for the instance, there are some “failed to load” errors right at the top for aqProf.dll, VtuneApi.dll, and VtuneApi32e.dll, and then a ton of warnings about unreadable Slate resource files. Attaching my log file in case someone more knowledgeable wants to take a look.

ue5blankstarter.log (152.8 KB)

OK final update, since the DLL issue is unrelated:

After disabling autostart for the two web servers in Project Settings → Plugins → Web Remote Control and then restarting the editor and Epic launcher, the issue disappeared, no workaround necessary.

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