I'm having trouble running Java; I keep getting a ClassNotFoundException error.
After updating to the latest version of Java (7.10), I'm unable to run Java at all. When detecting Java (http://java.com/en/download/testjava.jsp), I receive an error message and when I click, it says there is a ClassNotFoundException error. I've tried reinstalling Firefox, reinstalling this version of Java and a few older versions, trying Chrome and IE9, and in all cases, I've run into the same issue. On my add-ons, it appears like normal, and the installation works fine. Both:
- Next Generation Java Plug-in 10.10.2 for Mozilla browsers
- NPRuntime Script Plug-in Library for Java(TM) Deploy
Are enabled, alongside Browser Settings on the Java control settings, and I've cleared the cache as well. I've tried all the relevant fixes on http://java.com/en/download/testjava.jsp. I have absolutely no idea what to do. I've tried everything. Do any of you have suggestions?
Chosen solution
Hey all, I just wanted to post the solution I came to. I found another thread which solved my problem (https://forums.oracle.com/thread/2397610), in specific the last post. It boils down to this line:
"I have used the above trick of adding in control panel / Java / Java / View / Runtime parameters the value -Djava.net.preferIPv4Stack=true for my 2 JRE then saved then restarted my browser and suddenly it worked.*".
It suddenly worked for me too. Good luck!
Read this answer in context 👍 0All Replies (7)
Try to clear the Java cache.
- http://www.java.com/en/download/help/5000020300.xml - How do I clear the Java cache? - 1.5.0, 6.0
Control Panel > Java > General tab > "Temporary Internet Files" > Settings > Delete Files
- C:\Users\<user>\AppData\LocalLow\Sun\Java\Deployment\cache\
If that doesn't help then try to uninstall and reinstall 32 bit Java.
You can also look at this program to uninstall Java:
I've tried both.
Try to boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps in case some security software is interfering.
You can also try to uninstall the current Java 7 version and install the latest Java 6 version.
You can find the latest Java version on the Oracle website.
See Java Platform > Java SE 7U10 or Java 6U38 (Download JRE)
I have tried all of the above and still cannot get Java to work. do you have any other suggestions?
I cannot send out any email. Only receive it. HELP! I am desperate!
Hi p53colbert
Could you please start a new thread instead of posting in an existing thread?
Then you can provide more information like your operating system and installed extensions and installed plugins.
Make sure to have a 32 bit Java version in case you are on a 64 bit Windows platform.
Do you see the Java plugin in Tools > Add-ons > Plugins ?
Chosen Solution
Hey all, I just wanted to post the solution I came to. I found another thread which solved my problem (https://forums.oracle.com/thread/2397610), in specific the last post. It boils down to this line:
"I have used the above trick of adding in control panel / Java / Java / View / Runtime parameters the value -Djava.net.preferIPv4Stack=true for my 2 JRE then saved then restarted my browser and suddenly it worked.*".
It suddenly worked for me too. Good luck!