There are four possible reasons for this result:

cause #1:
The most likely reason for this behaviour is that you do not have Java installed on your computer.
You can download and install the Sun Java plug-in at this address:
http://www.java.com/en/download/manual.jsp

After installation, you can verify the running Java version at
http://www.java.com/en/download/installed.jsp

cause #2:
Another possible cause for this behaviour is that you do not have Java enabled on your browser.
To verify if this is the case, do the following in Internet Explorer 7 or 8:

Select the "Tools" Menu -> "Internet Options" -> "Advanced Tab"

Once you are in the Advanced Tab of the Internet Options dialog box, scroll down to the setting for: Java (SUN) To enable the Java Runtime Environment, check the "Use JRE 1.6….for <applet> (requires restart)" checkbox, this requires a restart of the browser, not of the computer:

If you do not see this option listed, then you do not have Java installed. Please refer to Cause #1 above.
Netscape and Opera ship with Java but it needs to be explicitly selected for installation during the browser installation.

Cause #3:
The third possibility is that you have both Microsoft and Sun's versions of Java installed and enabled on your computer and they are conflicting with one another.
To solve this issue, follow the steps in Cause #2 and select only one version of Java to use; Sun's or Microsoft's.

Cause #4:
The final possibility for this behavior is that your version of Java may be corrupt. To solve this issue, uninstall your current version of Java (Control Panel -> Add or Remove Programs -> Java …) and then download a new version from Sun following the instructions contained in Cause #1.

Back to top

Your web browser has a storage facility on your hard drive that stores graphics and text from web sites that you visit. This storage facility is called the cache, or Temporary Internet files. The reason web browsers have a cache is that it is quicker and easier to load images, applets, etc. from cache on your hard drive than downloading them again. Over time, your browser's cache gets full and the information gets outdated. This can cause problems with Java applets and can result in that Applets are freezing or not working at all. The solution to this is to clear cache and reload the page. If this does not work, try clearing your cache, closing your browser and then revisiting the page.

Internet Explorer 4.x or greater

1. Select Tools (or View if you are using IE 4.x), then click Internet Options.
2. Select the General Tab.
3. Click on the Delete Files button to clear the cache.
4. Remember to select the "delete all offline content" checkbox.

Netscape 4.x or greater

1. Select Edit, then click Preferences.
2. Select Advanced, then click Cache.
3. Click on Clear Memory Cache and Clear Disk Cache buttons to clear the cache.

Back to top

In case your are using Windows Vista, a newer Java Runtime Environment is required. Please uninstall your current JRE and install the latest version from http://www.java.com/en/download/manual.jsp.
You can verify your Java installation at http://www.java.com/en/download/installed.jsp

Back to top