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I've recently built a computer lab running various forms of Ubuntu. I'm testing out Edubuntu to see if it is a better fit for our school, but I'm running up against a problem I can't resolve.

One of the programs we use is Carnegie Learning Online, a Java program that I've managed to get working on both Ubuntu 10.04 and 12.04. After updating Java (all distros), when you access the website a .tt applet file is downloaded. With Java installed you can select the IcedTea plugin to open it.

On 10.04/12.04, this then opens a new window, Java runs a setup of some sort, and then a new window with the Carnegie program opens. On Edubuntu however, once you've told IcedTea to run it....nothing happens. No errors, just nothing. I've tried this with an older update of Java as well as the newest. Any ideas?

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First check that there are no hidden error screens. Sometimes child processes have trouble and the error or confirmation box does not get focus and it can only be found by minimising applications in the foreground. (in one case we came across here the confirmation box was on a different workspace - see the question on running rapidminer).

An alternative to iced tea might be to install the Oracle java JDK. have made a ppa for it you can use:

sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java7-installer

You might like to look at the relevant Webupd8 page.

If you still have a problem it might be necessary to remove the iced tea plugin.

Edit: I'm assuming that when you say "updated java" that you mean openJDK. Oracle changed their licensing so java can no longer ship with Ubuntu, or even be in any repository; hence the need for the webupd8 PPA.

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It might be better to link to our Java installation instructions instead of a 3rd party PPA. See:… – Jorge Castro Oct 10 '12 at 23:13
Hi Jorge, I'd agree but these instructions seem different, and yet also seem to link to the same instruction on… It's not clear to me why the instructions have been changed significantly compared to webupd8, especially when it refers to it. Also the 'best' answer by Foss Freedom may have been the best answer 1 year ago when it was written, but isn't the PPA much simpler and will be kept up to date? It seems complicated enough to put people off. – fabricator4 Oct 11 '12 at 0:54
We always strive to keep answers up to date; the accepted answer is pretty much the most straightforward way to do it. A 3rd party PPA isn't supported by Ubuntu, I just recommend you mention that up front before just recommending a PPA. – Jorge Castro Oct 11 '12 at 1:01
I will try both of these methods (I have two sandbox computers available to tinker with), but the one question I have is how to I remove the Iced Tea plugin that is already installed without a fresh install of the OS? – user95864 Oct 12 '12 at 23:23

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