# Unable to run Jenkins agents on Windows anymore?

**URL:** <https://community.jenkins.io/t/unable-to-run-jenkins-agents-on-windows-anymore/5552>\
**Category:** Using Jenkins\
**Created:** [February 1, 2023, 9:18am UTC](https://community.jenkins.io/t/unable-to-run-jenkins-agents-on-windows-anymore/5552 "2023-02-01T09:18:01Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![strich](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/strich/32/3252_2.png) [@strich](https://community.jenkins.io/u/strich)\
**Post date:** [February 1, 2023, 9:18am UTC](https://community.jenkins.io/t/unable-to-run-jenkins-agents-on-windows-anymore/5552/1 "2023-02-01T09:18:01Z")

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Hey folks. I’m coming back to Jenkins after about 2 years and I’m a bit lost with how agents are meant to work now. Previously, I used to be able to download and run the agent java file to keep agents alive (Windows). Now when I do this I get only a jlnp config file? I noticed that maybe I need agent.jar too and try to run it with:  
`java -jar agent.jar -jnlpUrl http://[URL]/manage/computer/AGENT%5FID%5F33/jenkins-agent.jnlp -workDir "C:\GameRigger"`  
However I get the following error on Windows:  
`Exception in thread "main" java.lang.UnsupportedClassVersionError: hudson/remoting/Launcher has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0`  
Which confuses me coz the Java version is fully up to date on the Windows client (Java v8 361). Any help would be appreciated!

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**Author:** ![PierreBtz](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/pierrebtz/32/55_2.png) [@PierreBtz](https://community.jenkins.io/u/PierreBtz)\
**Post date:** [February 1, 2023, 9:55am UTC](https://community.jenkins.io/t/unable-to-run-jenkins-agents-on-windows-anymore/5552/2 "2023-02-01T09:55:32Z")

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You didn’t include the version of Jenkins you use but latest are not compatible with Java 8 anymore.

In the error message:

> class file version 55.0

This is Java 11.

> this version of the Java Runtime only recognizes class file versions up to 52.0

This is Java 8.

So update the jdk you use on your agent to a jdk 11.

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**Author:** ![strich](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/strich/32/3252_2.png) [@strich](https://community.jenkins.io/u/strich)\
**Post date:** [February 1, 2023, 9:57am UTC](https://community.jenkins.io/t/unable-to-run-jenkins-agents-on-windows-anymore/5552/3 "2023-02-01T09:57:11Z")

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Thanks Pierre! I actually just figured this out myself moments ago - Seems we need to install JDK 11 instead of JRE now.