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How do I install Firefox version 51 on my computer so that Java will work.

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  • Last reply by James

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We have to upload a disk on a website that uses a Java plugin. According to the Java site, Firefox versions 52 and newer do not support it. Therefore, we need to install version 51. We cannot find a legitimate way to do this. Please urgently advise.

We have to upload a disk on a website that uses a Java plugin. According to the Java site, Firefox versions 52 and newer do not support it. Therefore, we need to install version 51. We cannot find a legitimate way to do this. Please urgently advise.

Chosen solution

https://support.mozilla.org/en-US/kb/npapi-plugins

The most current version that still allows other NPAPI Plugins besides Flash Player to run is Firefox 52 ESR. The current version is 52.8.0esr. The last major update 52.9.0esr will be out on June 26th and will be EOL on Sept 5. It only gets security and allowed stability fixes and will be much more safer to use over the rather old 51.0 with unpatched vulnerabilities.

Note since you use Windows you will need the 32-bit version as the Win64 version has only allowed the Flash Player and Silverlight NPAPI Plugins to run since version 43.0 (Win64 started at 42.0 Release). Also note, download the Java 8 and not the newer 9 as Oracle is discontinuing their vulnerable Java Plugin.

https://www.mozilla.org/firefox/organizations/all/#legacy

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Is this ESR or standard FF? With the latest version of FF java is only used when the site uses it otherwise it doesn't load. Also if you plan to use java make sure to use the latest Java version as well.

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Hi. This is just standard FF. We are using the latest version of Java. On the Java website, however, it says that Java is not supported in FF after version 52. So, it seems like the easiest way to make it work would be to download an older version. How do we download version 51 (or earlier)? Thank you.

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Chosen Solution

https://support.mozilla.org/en-US/kb/npapi-plugins

The most current version that still allows other NPAPI Plugins besides Flash Player to run is Firefox 52 ESR. The current version is 52.8.0esr. The last major update 52.9.0esr will be out on June 26th and will be EOL on Sept 5. It only gets security and allowed stability fixes and will be much more safer to use over the rather old 51.0 with unpatched vulnerabilities.

Note since you use Windows you will need the 32-bit version as the Win64 version has only allowed the Flash Player and Silverlight NPAPI Plugins to run since version 43.0 (Win64 started at 42.0 Release). Also note, download the Java 8 and not the newer 9 as Oracle is discontinuing their vulnerable Java Plugin.

https://www.mozilla.org/firefox/organizations/all/#legacy