Java Installation
Applicable to
2.x
3.x

In some cases, you may be presented with an error dialog relating to an unsupported Java version or the application may not launch at all. In these cases generally follow these steps:

  1. Uninstall all Java versions on your system (JREs and JDKs)
  2. Reinstall the recommended version of Java (see below)
System Path and JAVA_HOME
Always ensure that the System Path and JAVA_HOME are configured during the installation (they may be unchecked within the installer if prior versions mis-configured these properties and failed to remove them upon uninstallation. This issue typically does not apply to Linux users.

Generally, you should avoid installing older versions as well (such as Java 8). Typically applications operate fine on newer versions (especially as games like Minecraft ship their own versions of the Java runtime along with the game). Older installations may clash and (in case of Oracle's versions) fail to properly register with your system.

Installing older Java Versions
If you really need an older version of Java installed on your system, install it last and ensure these installations do not configure JAVA_HOME and are not present within the system path (these options are typically presented within your installer). Linux users may need to consult their respective distribution's documentation on how to select the default installation.

If the issue persists, please seek assistance via the support channels.

Java Versions

At the time of writing, the recommended Java distribution is AdoptOpenJDK in version 11 (choose the HotSpot based implementation for maximal compatibility). Newer versions of AdoptOpenJDK may also work without issues but are currently not recommended due to API changes within version 15 of the specification.

Oracle versions should generally be avoided as their installers traditionally caused serious issues regarding the registration of the Java installation within the System Path (as well as the creation of the JAVA_HOME environment variable).