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Java Troubleshooting guide

Java Troubleshooting guide

Verify that the browser you are using has Java enabled.

Internet Explorer

  1. Click Tools and then Internet Options
  2. Select the Security tab, and select the Custom Level button
  3. Scroll down to Scripting of Java applets
  4. Make sure the Enable radio button is checked
  5. Click OK to save your preference

Chrome users

  1. Enter about:plugins in the search field.
  2. In the Plug-ins list, look for Java and check whether Java is enabled (if the Disable link appears, Java is already enabled)
  3. Click on the Enable link (if available)
  4. Check the Always allowed box to stop additional Chrome warnings


Check that Java is enabled through the control panel

  1. In the Java Control Panel, click the advanced tab.
  2. Under “Default Java for browsers” Microsoft Internet Explorer should be enabled by policy.
  3. If this is not enabled, uninstall Java, Reset IE to defaults and re-install the packaged version of Java from the master packages folder.
  4. Restart the machine to enable the changes.
  5. Try to replicate the issue.


Delete Temporary Files through the Java Control Panel

  1. In the Java Control Panel, under the General tab, click Settings under the Temporary Internet Files section.

    The Temporary Files Settings dialog box appears.

  2. Click Delete Files on the Temporary Files Settings dialog.

    The Delete Files and Applications dialog box appears.

  3. Click OK on the Delete Files and Applications dialog. This deletes all the Downloaded Applications and Applets from the cache.
  4. Click OK on the Temporary Files Settings dialog.

Note: If you want to delete a specific application and/or applet from the cache, click on View Button.


Check for/Remove multiple or older versions of Java

  1. Click Start, click Control Panel
  2. Double click the Add/Remove Programs control panel icon.
  3. This will display a list of software on your system, scroll down to the “Java” section.
  4. If multiple versions of Java are listed, uninstall all of them. (Do not remove anything besides Java)


Check for/Remove multiple or older versions of Java

  1. Open Windows Explorer
  2. Browse to Computer > System (C:) > Program Files.
  3. Scroll down to and open the “Java” folder
  4. If multiple versions of Java are listed, delete any folders which do not match with the current installed version above. (Make sure you have a backup of these folders before deleting)


Configure Proxies through the Java Control Panel

  1. In the Java Control Panel, under the General tab, click on Network Settings.
  2. Select the Use Proxy Server checkbox.
  3. Enter an Alternate PROXY Server, into the Address: field.
  4. Set the port to 8080
  5. Click the Advanced button
  6. Check the Use same proxy server for all protocols checkbox.
  7. Close all browser windows. Restart the browser and try to replicate the issue.
  8. If the applet still does not load and you see the same connection error, try Enable and Review the Java console for more details.

Note: A common errors that is seen if the proxy settings are not correct:
While application is starting, a dialog like this appears including “ClassNotFoundException” or “ConnectionTimeout”


Enable and Review the Java console.

Enable the Java Console in the Java Control Panel

  1. In the Java Control Panel, click the advanced tab.
  2. Expand the Java console option.
  3. Select Show Console and click OK.

Enabling the Java Console through the Java icon in the Windows system tray

NOTE: These instructions apply if the place Java icon in the system tray is enabled through the Java Control Panel (Advanced tab)

  1. Locate Java icon in the System tray
  2. Right click on Java icon
  3. Select Open Console.

Once enabled, Attempt to replicate the issue, when you launch the Site or Java app again, you will notice that a new window will also open which is the Java Console. Once you’ve replicated the behaviour, you can use the Copy button to copy the contents of the java console which can then be pasted into a text file for review.


Manage the Exception Site List

Add a URL

  • Click on the Edit Site List button.
  • Click the Add in the Exception Site List window.
  • Click in the empty field under Location field to enter the URL.
    URL should begin with http:// or https://
    eg. or
  • Click OK to save the URL that you entered. If you click Cancel, the URLs are not saved.
  • Click Continue on the Security Warning dialog.

Important: Only add a site to the exception site list if you trust the entire site. Even if a path is specified, adding a site that might contain other untrusted paths could present a security risk and is not recommended.