# Is there a way I can get the agent.jar to work with jdk5 or jdk6? **URL:** \ **Category:** Ask a question\ **Tags:** question\ **Created:** [June 9, 2022, 4:35am UTC](https://community.jenkins.io/t/is-there-a-way-i-can-get-the-agent-jar-to-work-with-jdk5-or-jdk6/2683 "2022-06-09T04:35:48Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![MikeyCarter](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/mikeycarter/32/349_2.png) [@MikeyCarter](https://community.jenkins.io/u/MikeyCarter)\ **Post date:** [June 9, 2022, 4:35am UTC](https://community.jenkins.io/t/is-there-a-way-i-can-get-the-agent-jar-to-work-with-jdk5-or-jdk6/2683/1 "2022-06-09T04:35:48Z")
I know I’m beating my head against a wall with this… but I was trying to connect windows 98 up to jenkins as a slave just as a dumb challenge. Got jdk 1.5 install but hit unsupported class version error, when trying to connect via jnlp. So what’s the oldest version of the agent.jar I can get working with jenkins that works with either jdk 1.5 or jdk 1.6? ---
**Author:** ![halkeye](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/halkeye/32/8_2.png) [@halkeye](https://community.jenkins.io/u/halkeye)\ **Post date:** [June 9, 2022, 7:05am UTC](https://community.jenkins.io/t/is-there-a-way-i-can-get-the-agent-jar-to-work-with-jdk5-or-jdk6/2683/2 "2022-06-09T07:05:19Z")
We can barely support the most recent of releases so I wouldn’t expect much. I believe we’ve been java 8 maybe 7 since 2.x so probably early 1.x line, or maybe even Hudson ---
**Author:** ![poddingue](https://dub1.discourse-cdn.com/flex013/user_avatar/community.jenkins.io/poddingue/32/985_2.png) [@poddingue](https://community.jenkins.io/u/poddingue)\ **Post date:** [June 13, 2022, 7:45am UTC](https://community.jenkins.io/t/is-there-a-way-i-can-get-the-agent-jar-to-work-with-jdk5-or-jdk6/2683/3 "2022-06-13T07:45:37Z")
Hello @MikeyCarter and welcome back to the community 👋 You may want to try installing a later version of Java: [Sun Java Runtime Environment - KernelEx Wiki](http://kernelex.sourceforge.net/wiki/Sun_Java_Runtime_Environment#:~:text=The%20last%20version%20officially%20supported,can%20install%20version%206.0_xx). . Good luck with that. ---
**Author:** ![Ian\_W](https://avatars.discourse-cdn.com/v4/letter/i/cab0a1/32.png) [@Ian\_W](https://community.jenkins.io/u/Ian_W)\ **Post date:** [June 14, 2022, 9:55am UTC](https://community.jenkins.io/t/is-there-a-way-i-can-get-the-agent-jar-to-work-with-jdk5-or-jdk6/2683/4 "2022-06-14T09:55:46Z")
Java 1.5 is the [last supported](https://www.oracle.com/java/technologies/javase/system-configurations.html) release on [Windows 98](https://en.wikipedia.org/wiki/Windows_98) (ie: 1998, or 199-05-05 for 98SE) Not supported on [SE 6](https://www.oracle.com/java/technologies/system-configurations.html). The last public release of Java 1.5 was [jdk-15\_0\_22](https://www.oracle.com/java/technologies/javase/releasenotes-v150.html#150_22), 2009-10-09 And the Extended Support release was [jdk-15\_0\_85](https://www.oracle.com/java/technologies/javase/advancedv5-support-relnotes.html), 2015-04-09, Though probably not on Win98 SE since support for the OS ended on 2006-07–11. The oldest Jenkins LTS release is [1.409.1 (2011/06/06)](https://www.jenkins.io/changelog-stable/#v1.409.1), which is two years after the the last public jdk1.5 release This [commit from Koshuke](https://github.com/jenkinsci/jenkins/commit/3431a7cba), Jun 15, 2013, pushed Jenkins core to jdk1.6. It was tagged 1.565.1-rc1, [released 2014-07-30](https://www.jenkins.io/changelog-stable/#v1.565.1) Less than a year later, Koshuke and Jenkins said [goodbye to Java 6](https://www.jenkins.io/blog/2015/04/06/good-bye-java6/). So, without [hacking things](http://kernelex.sourceforge.net/wiki/Sun_Java_Runtime_Environment#:~:text=The%20last%20version%20officially%20supported,can%20install%20version%206.0_xx), I’d say you are not likely to get anything newer than 1.565.1 (so 1.554.3 (2014/06/30) ) to work at all. And my dumb challenge was pulling this response together!