Frequently Asked Questions

Where do I download Reality Loader?

Reality Loader is embedded into RealityHub. To download it:

  • Login to RealityHub UI, go to Main Menu > Configuration

  • On the left menu, select General > Configuration

  • Go to Maintenance > Reality Loader and click on the Download

Also visit: Reality Loader

Is it essential to keep RealityHub and Reality Loader versions the same?

Yes. It doesn’t matter if you upgraded or downgraded RealityHub; it is essential to keep RealityHub and Reality Loader versions the same.

I can’t access the Nodegraph menu and receive a warning: “Engine must be running and fully loaded.”

If you receive such a warning, check if the Reality Loader is running.

Can I reach my Projects and Assets if they are on a different server?

You can keep projects and assets on different servers if your system meets the recommended system requirements.

You may also want to check the Shared DDC workflow.

How can I list the Project cache?
  • Go to the General Setting and activate the Configuration module

  • Click on Engines > Hosts

In the right panel, there is a Cache tab. You can list & delete your cached project in this section.

What is RealityHub Community Edition?

Community Edition is a free-to-download version of RealityHub that can be utilized by students, artists, and developers to create personal projects.

See also

Which features are available with the Community Edition?

You can utilize Reality Engine or Unreal Engine, create Cook requests, and use the REST API. Modules like Nodegraph Editor, Playout, Launcher, Form Builder, Action Timeline Editor, and Cook Manager are available along with the Advanced Preview Monitor.

Community Edition works only with a single Local Engine.

Can I upgrade my Community Edition?

It is possible to upgrade the Community Edition without uninstalling/reinstalling the current version. Zero Density Licensing Team will issue your licenses when the license purchase procedure is successfully finished.

For any inquiries, please get in touch with the Licensing Team via

Is Community Edition license time-bound?

Yes. When the Community Edition expires, either you have to upgrade the version or create a request to license it.

Can I use different browsers to reach the same RealityHub Server?

You can use any of the supported browsers of your choice harmoniously.

Which Engines are supported by RealityHub?

RealityHub 1.3 supports the following Engines:

  • Reality Engine 4.25

  • Reality Engine 4.26

  • Reality Engine 4.27

  • Unreal Engine 4.27

  • Unreal Engine 5.0

Update: If you use RealityHub 1.3.2, you can also control Unreal Engine 5.1. See Controlling Unreal Engine 5.1

I defined the Shared Folder Path, User Name, and Password, but I can’t reach my project, and ReScan operation fails.
  • Check if the folder structure or folder name has changed.

If the abovementioned step does not help:

  • Check if your Windows username is under a corporate domain. Example: CORP\name.surname

If it doesn’t help:

  • Check if you have administrative privileges to reach your shared folder.

See Project Configuration

What is the meaning of the “Please match the requested format” when I try to add New Shared Folder?

For a Shared Folder, only the UNC Path is supported. If you try to add a Local Path name, you will be asked to write the requested format.

  • UNC Path Example: \\\RealityWorkspace\Reality\Assets

  • Local Path Example: C:\RealityWorkspace\Reality\Assets

Can I install different applications on the RealityHub Server?

We strongly advise you not to install any application on the RealityHub server; it might cause substantial problems.

To set an example, the application you installed might try to use one of the Ports dedicated to RealityHub and disrupt your communication with your production pipeline. It is untested, uncertified, and inadvisable.

I can’t see my project in the Launcher.

In such cases, you need to scan the folder where you keep your Projects by using the Scan Folder tool.

Is it possible to grant single module access to a specific user or user group?

With the Advanced User Management module, you can restrict/grant access to different modules/features.

I upgraded the RealityHub from 1.1.x to 1.3, and now I can’t reach any module except for User Management and Configuration modules.

With version 1.3, we introduced a new module for user management. The new User Management Module offers two different models: Advanced User Management and Basic User Management. We advise you to create an administrator account and leave the admin for only essential administrative purposes.

For more information, please visit User Management

I can’t access a specific module, like Nodegraph/Actions.
  • If your company uses Advanced User Management, contact your system admin if your Policy allows you to use a specific module.

  • Check if the License is reserved for other users. See License Reservation

  • If you meet the above requirements, refresh the page.

  • If it doesn’t help, restart the RealityHub Service.

If the abovementioned steps don’t help, please get in touch with our Support Department.

Can I reach RealityHub Server via a supported browser but from different operating systems like Ubuntu or macOS?

You can control your RealityHub from a supported browser if your operating system fully supports the requirements.

Can I install RealityHub Server on Ubuntu or macOS?

RealityHub Server can only be installed on Microsoft Windows. Please visit System Requirements

I received a “Couldn’t connect to WebSocket server” error.

Contact your IT if:

  • Your network is working properly.

  • The corporate network has a different problem.

  • The servers are upgraded.

If it doesn't help:

  • Refresh the page and try to re-login

If you can't obtain a viable result:

  • Check if the RealityHub admin has logged you out from the system via Force Logout. See also User Management

If you can't find your solution in the abovementioned steps, please contact our Support Department

Can I change the values of identical nodes located inside multiple Engines?

You can utilize Gang Mode for this purpose. It is a handy feature when conducting RGraph operations over multiple-engine configurations.

Can antivirus software affect RealityHub?

We do strongly recommend you give full exception to RealityHub independently of your security toolset.

Would it be a problem if I used the certified Microsoft Windows version with a different language pack?

For RealityHub Server, only English (United States) is tested and certified. Using other languages may negatively affect the functionality of the RealityHub Server side.

What is the meaning of "RGraph history is not tracked in live mode"

When your Launch Configuration is set to Live, RGraph history entries are not tracked. To activate the RGraph History, make sure that you change the Launch Mode from Live to Configuration.

Does RealityHub support undo action via CTRL + Z keyboard combination in the Nodegraph operations?

To undo your latest step, you can utilize RGraph History.

Can I use browser extensions along with RealityHub?

We do not certify or recommend the use of browser extensions. Installing a browser extension might affect your production.

I received a "Failed to retrieve path source" error message

In such a scenario, check if the folder you want to access is still reachable on your network.

I received a "Failed to launch studio" error message

In such a scenario, check if your Reality Loader and RealityHub versions match.

How can I perform a clean install?

A clean installation refers to the process of installing an application without carrying over any data or settings from a previous installation.

Please be aware that this process requires you to erase all existing RealityHub data; therefore, we strongly recommend you back up your data for any undesired outcome. Please visit Database Backup and Restore

To perform a clean install:

  • Close the Reality Loader and RealityHub browser tab

  • Go to Windows Services and stop RealityHub Service and RealityHub Database services

  • Uninstall the RealityHub Server and then Reality Loader

  • Go to C:\ProgramData\Zero Density

  • Delete RealityHub & Reality Loader folders

  • Proceed new installation. See also Installation and Configuration

What are the necessary port numbers for a default RealityHub installation?
  • Reality Loader (Engine) <-> RealityHub (Server) Connection: Port 6001 (This port is fixed for communication between the RealityHub Server and the Reality Loader).

  • RealityHub Web GUI: Port 80 (This is the default port and remains unchanged during installation).

  • Reality Engine: Port 6666 (Default port for the Reality Engine server).

  • RealityHub Database: Port 5433 (Default port for the RealityHub Database connection).

  • CII Server: Port 1235 (Default port for the CII Server connection).

  • Reality Hub to the License Server: TCP Port 443

See also:



What are the general recommendations for Windows policies?

Ensure that no policies are implemented that may disrupt general operations. This includes enabling the firewall or antivirus, conducting aggressive file and folder scanning during unpredictable days and hours, and initiating non-certified Windows and other driver updates.

What is the RealityHub's relation with Windows or third-party firewall?

In cases where use of firewall is mandatory, ensure that connections between RealityHub and the Engine clients are permitted by the firewall, and include the following folders in the exception list of your antivirus software:

  • C:\ProgramData\Zero Density

  • C:\Program Files\Zero Density (Two folders)

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