Windows Installation

This guide covers installing and running a PowerNukkitX server on Windows 10 or Windows 11.

Prerequisites: Java 21+

PowerNukkitX requires Java 21 or newer (64-bit). Older versions of Java will prevent the server from starting and produce errors like UnsupportedClassVersionError.

1. Download Java 21

• Download the Windows MSI installer for Eclipse Temurin JDK 21 from the Adoptium Releases Page.
• Run the .msi file and follow the setup wizard. Make sure to check the option to "Set JAVA_HOME environment variable" and "Associate .jar files" during installation.

2. Verify Installation

Open a new Command Prompt (cmd) or PowerShell window and run:

java -version

You should see output indicating version 21 (e.g., openjdk version "21.x.x").

Setting Up the Server

1. Create a Dedicated Folder

Create a folder on your system where your server files will reside (e.g., C:\PNX-Server).

[!CAUTION] Avoid creating your server folder inside protected system directories like C:\Program Files or C:\Windows, as Windows security permissions may prevent PowerNukkitX from generating files (worlds, configurations, logs).

2. Download the Server JAR

Download the latest powernukkitx.jar from the Official PowerNukkitX GitHub Releases Page and place it into your server folder.

3. Create the Startup Script

PowerNukkitX requires specific Java reflection access parameters (--add-opens) to load its registry and plugins correctly. You should create a startup script instead of launching the jar file directly:

1. Inside your PNX-Server folder, right-click, select New > Text Document, and name it start.txt.
2. Open start.txt in Notepad and paste the following content:

   @echo off
   java -jar --add-opens java.base/java.lang=ALL-UNNAMED --add-opens java.base/java.io=ALL-UNNAMED powernukkitx.jar
   pause

3. Save the file and close Notepad.
4. Rename the file from start.txt to start.bat. Make sure file name extensions are visible in File Explorer (View > Show > File name extensions) so that you change the actual extension, not just the name.

Launching the Server

1. Double-click start.bat to run the script.
2. First-run Wizard: A command window will open. If it is your first time starting the server, follow the console setup prompts to:
   • Accept the license by typing y.
   • Select the server language (e.g., eng for English).
   • Enter your server's MOTD (name) and listening port (default is 19132).
3. Once completed, the server will generate the pnx.yml file, create the default world folder, and load the Bedrock network listener.
4. To stop the server safely, type stop in the console and press Enter.

Troubleshooting Windows Setup

Command 'java' is not recognized

Your system cannot locate Java. Ensure Java 21 is installed. If it is installed but you still see this error, you need to configure your environment variables:

1. Search for "Edit the system environment variables" in the Windows Start Menu.
2. Click Environment Variables....
3. Under System variables, check if JAVA_HOME exists and points to your JDK 21 folder (e.g., C:\Program Files\Eclipse Adoptium\jdk-21.x.x\).
4. Find the Path variable in System variables, select it, click Edit..., and make sure it includes %JAVA_HOME%\bin (or the direct path to adoption bin folder).
5. Restart your Command Prompt or PC for changes to apply.

Port binding error (BindException)

If you see java.net.BindException: Address already in use, it means another application (or another instance of the server) is running on port 19132.

• Check if you have another Command Prompt window running the server and close it.
• Alternatively, edit pnx.yml to change port to a different number (e.g. 19133).