Go to Tools>Internet Options>Security tab>Click Custom Level>Scroll down to 'Scripting'>Active Scripting should be 'Enable'>OK>Advanced tab>scroll down to 'Java (Sun)' and make sure the box is checked and it says 'JRE 1.6.0_01>OK>Restart if you had to check the box.
To check to see if you already have Sun Java installed and properly enabled, you may use the steps below:
1. Click on the Start button.
2. Click on Run.
3. Type control in the text field and click OK.
4. This will open the Windows Control Panel.
5. Once you are viewing the Windows Control Panel there is panel to the left with a link that either says 'Switch to Classic View' or 'Switch to Category View'. If it says Switch to Classic View then click that link.
6. If it says 'Switch to Category View' then you are where you want to be.
7. To the right of where it says 'Switch to Category View' you will see a list of items. Double-click on Java in the list so the Java Control Panel appears.
8. In the Java Control Panel click the Advanced tab.
9. If you don't see the 'Advanced' tab you have an older version of Sun Java. You will need to update to Java version 6 Update 1 to make sure everything is working properly. Once you do this, Sun Java will automatically be enabled.
http://www.java.com/en/download/windows_ie.jsp
10. Once you are in the 'Advanced' you will want to click the plus sign (+) next to where it says Applet tag support.
11. There you will see a check box next to 'Internet Explorer' and/or 'Mozilla Netscape'.
12. If you have Internet Explorer then make sure the box next to it is checked.
13. If you have a Mozilla browser, like Netscape or Firefox, then make sure the check box next to the 'Mozilla Netscape' option is checked as well.
14. Then click OK at the bottom of the Java Conrol Panel window and close all of your browser windows.
Once you are sure you are using the latest version of Sun Java, please follow these instructions to delete the Java cache and objects if you're using Windows.
Click the following things in order: Start -> Control Panel ->Swithch to Classic View->Java -> 'General' tab.
Then, click the Delete Files button located in the Temporary Internet Files section. There may be a Setting button, if so, click it and then the Delete Files button.
Next, make sure all the boxes are selected, and click OK.