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Hi can you help? I'm having great trouble launching Java applets using Windows 7 64 bit. I have the 32 bit version of Java installed (as recommended, for use with 32 bit browsers). When I click on an Java applet to open it the Java logo shows with a circular progress bar, but the process goes no further, just the progress bar going round and round. There are no error messages. The computer is a few months old and Java has never worked properly. I've tried with both IE9 and Chrome, followed the suggested fixes, uninstall then reinstall, check certain browser settings (all were in order), check Java control panel settings (again all was in order) delete the internet cache etc, tried 32bit & 64bit Java side by side. All to no avail.

I'm baffled

Is there anything else to try, or do I have to accept a computer without Java (Very inconvenient!)


EDIT If the Java applet is left to load for long enough then eventually the error message 'ClassNotFoundException'is given.

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Can be a problem with applet as well....check some other applet... – tumchaaditya Aug 30 '12 at 9:30
Is it always the same applet or site? The site could possibly be misconfigured. – dangowans Sep 17 '12 at 22:41
Are you behind any sort of firewall that may be blocking "JAR" files? – dangowans Sep 17 '12 at 22:42

You did not say what environment you are working in...home, small office, corporate?

The problem is authentication between the client and server. In Windows XP this defaulted to NTLM. Now with Win7 it defaults to Kerberos and NTLMv2, which the JRE/IIS/IE does not quite handle.

I have found that upgrading the JRE to JRE 7u8 or later resolves this, although the initial authentication can take quite a while.

There is an alternative if you have permission to regedit the workstation and the server(s), but would prefer not to release this in the clear.

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