Sunday, January 4, 2009

Fix Java in Firefox on 64-bit Windows 7 or Vista

Note: This post was originally written for Windows Vista 64-bit and Firefox 3. It still applies to Windows 7 64-bit and Firefox 3.5.

I recently installed Windows Vista Business 64-bit, then installed the 32-bit version of the Java Runtime Environment (JRE), and was amazed to find that it didn't work in Firefox 3. All I got was a blank space where the applet should have loaded.

Because there's no official 64-bit version of Firefox 3, I'm running the standard 32-bit edition (it works fine on 64-bit Windows). So, I need the 32-bit version of the Java RE. Here's how to make it work:
  1. Copy the following files from C:\Program Files (x86)\Java\jre6\bin\ to C:\Program Files (x86)\Mozilla Firefox\plugins:
    • npjpi160_11.dll (last 2 digits are the update version)
    • npoji610.dll,
    • npt.dll
  2. Open the Java test page to verify that it works.
Each time Java or Firefox updates to a new version, you'll have to copy the latest files from C:\Program Files (x86)\Java\jre6\bin\ to C:\Program Files (x86)\Mozilla Firefox\plugins.

If you haven't yet installed Java, or the steps above don't work, try this:
  1. Uninstall any existing version of Java from Control Panel, Programs and Features.
  2. Delete any Java plugins from C:\Program Files (x86)\Mozilla Firefox\plugins. These are usually named np*.dll, but you can check which ones are Java-related by checking the file properties.
  3. Download the latest version of Java from Sun (or download the offline Java installer) At the moment, this is Java 6 Update 11.
  4. Try the first set of steps above.
Sources

17 comments:

Anonymous said...

Thanks for putting this out there. Helped fix a problem I had running 32-bit Java+Firefox on 64-bit Windows 7.

warnerchad said...

You're welcome! That's the reason I put technical posts on this blog; to spare others from the trouble I endured.

Sami Näätänen said...

Well I simply skipped to the copying part, as I only had installed the latest Java. This seamed to be enough.

Tony said...

Beautiful! It is incredible how much speculation and misinformation is out there about this problem! It all boils down to the fact that the Java installer does not copy the three necessary files to the Firefox plug-ins directory! Thanks a million for figuring this out and posting it.

Anonymous said...

thanks it worked!

lucky644 said...

Thank you, this worked perfectly!

Anonymous said...

thanks!

Anonymous said...

Thanks a lot. It's ridiculous that this problem still exists. Every time Java updates itself it seems to break in FFX again.

Anonymous said...

Thanks a ton, wish I'd found your post sooner.

Jon said...

I wish I had found your post 3 days ago! Java had worked fine for me on my new Vista64 machine with Firefox3, then Java decided to update itself... Thanks again, worked like a charm.

Ryster said...

Thanks also, I was pulling my hair our trying to figure out why this wasnt working. I reinstalled Java several times, as well as Firefox. In the end I did some google searching in desperation and found your blog post. Thanks! Annoying that Sun haven't fixed this blatant bug yet.

cbdoc said...

Thanks very much for the great and concise guide - Firefox works under W7-64 now!

Cheers.

Tim said...

Much appreciated mate. I must have trawled 20 pages all telling me the wrong info before I found this.

Dead said...

Oh wow finally!! Thank you bro this worked great, I was googling trying to find a solution to this and finally found one. Thanks again!

Mattias said...

Thanks a million! So easy and yet so difficult if you're not an expert.
This is a perfect example of how the free internet community should work!

Anonymous said...

Thanks, worked great with update 13

Anonymous said...

I've posted this issue in the JAVA forums and we'll see their reply. (i.e. How to permanently fix, but it's really annoying)

http://forums.sun.com/thread.jspa?messageID=10726832&#10726832