Installing FLUKA/Flair on Windows 10 using WSL

It is recommended to use the Windows Subsystem for Linux (WSL) for running CERN's FLUKA and Flair on Windows 10. The Windows Subsystem for Linux lets developers run GNU/Linux environment - including most command-line tools, utilities, and applications - directly on Windows, unmodified, without the overhead of a virtual machine.

1. Required software

1.1. Windows Subsystem for Linux

Windows Subsystem for Linux requires Windows 10 (build: 16299 [2017 Fall update] or greater) and admin rights during installation.

1.1.1. Enable Windows Subsystem for Linux

Start a PowerShell as Administrator and run the following command:

Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Windows-Subsystem-Linux

When the command asks, reboot the PC to finalize the installation.

1.1.2. Get Ubuntu Linux from the Microsoft Store

In the Microsoft Store, search for Ubuntu 18.04 and click on the Get button, then on Install.

1.1.3. Initialize Ubuntu

To initialize simply click Launch in the Microsoft Store, or find Ubuntu in the Start Menu.

After a couple minutes it will ask for a new Linux username and password. They can be anything, as they are not related to your Windows credentials.

After the initialization, Ubuntu works just like a native Ubuntu 18.04 system.

1.1.4. Legacy console error

Sometimes you can't enter the new Linux username and password, and the following error message is appearing:

Unsupported console settings. In order to use this feature the legacy console must be disabled.

To solve this, right click on the Title bar of the windows of Ubuntu, and select Properties. On the Options tab disable the Use Legacy Console option, and click OK. To apply the change you have to close Ubuntu.

To restart the initialization, Ubuntu has to be reset. See 5. for instructions. When it is finished, start Ubuntu again, to start the initialization again.

1.1.5. Accessing files in WSL

The windows drives (C:\, D:\, etc.) are automatically mounted at: /mnt/<drive_letter>/...

1.2. Install Xming

Xming X Server for Windows is necessary to visualize the Flair's graphical interface.

Download and install the Public Domain Release version from

2. Installing FLUKA and Flair

2.1. Setting up Ubuntu and install Flair

Download the script from here (Right click, save link as ...). In the Ubuntu terminal change the directory to the downloaded script and run the following command:

sudo ./

The script will install the necessary packages and Flair.

2.2. Download and install FLUKA

Download the GNU/Linux *gfor7_amd64.deb package of FLUKA from

The steps of the installation can be found here.

3. Running FLUKA and Flair

3.1. Running Xming

Start the Xming app from the start menu.

3.2. Running Ubuntu

Launch Ubuntu from the Start menu

3.3. Running FLUKA and Flair

See the instructions on

4. Updating FLUKA and Flair

4.1. Update Flair

To update Flair (and Ubuntu as well) run the following commands:

sudo apt-get update
sudo apt-get install flair flair-geoviewer

To update the whole Ubuntu system use

sudo apt-get upgrade

as well.

4.2. Update FLUKA

Manually install the latest package of FLUKA.

5. Resetting WSL

If there is an issue with WSL, you can always reset it to a clean state. To do so search for Ubuntu in the Start Menu, right click on its icon, and select (More) App settings. In the new window click the Reset button. When the reset is complete close the settings window and restart Ubuntu.