Error "A Java exception has occurred"

[lemaximedu66]

very descriptive thx java lmao

[kaklakariada]

Hi @lemaximedu66 ,

It looks like you are using an old version of Java. Please download a newer version, for example 21 from https://adoptium.net/temurin/releases/?package=jre and install it.

[kaklakariada]

If this does not work, please start PortMapper on the command line:

java -jar portmapper.jar

This should output a more helpful error message.

[lemaximedu66]

idk why but it works with the "java" command wtf

[lemaximedu66]

im confused

[lemaximedu66]

Hi @lemaximedu66 ,

It looks like you are using an old version of Java. Please download a newer version, for example 21 from https://adoptium.net/temurin/releases/?package=jre and install it.

i updated it less than 1-2 months ago

[kaklakariada]

OK. It looks like your Windows uses two different Java versions: it uses Java 8 when double clicking the .jar file, but the Path environment variable points to java command from Java 19.

You could

1. Uninstall Java 8 and Java 19 and install Java 21 and try to double click again
2. Create a small .bat file containing the java -jar command und use that for starting PortMapper.

[lemaximedu66]

thats weird cuz when you go on java.com it makes you download the first version (the java 8 thing) and i think the other is called Java Developpment kit or something and it isn't offered on java.com and i also think minecraft won't run on jdk

[kaklakariada]

That's strange. Java 8 is deprecated since a long time and not supported any more. I recommend downloading from https://adoptium.net/temurin/releases/?package=jre&os=windows

PortMapper needs Java 11 or later.