University of California, Riverside

iLearn Support


Java software is used to run many of the applets and tools used within Blackboard. It is necessary for users to have an up-to-date JRE (Java Runtime Environment) installed and functioning in order to access and use these Blackboard features.

IMPORTANT NOTE: Due to recent security concerns with Java, Java may be blocked in your operating system or browser settings. To re-enable it temporarily, refer to STEP 2-to locate your OS, and follow the steps to make sure it is enabled there. Then under STEP3-locate your browser and follow the steps shown to make sure it is enabled there.

If the System Test reports a problem with the Java installation on your computer, first verify the problem by visiting this alternative test site:
If that site indicates Java is installed and working correctly, there is no need to do anything further.
If that site indicates Java is not installed or not working, refer to the following troubleshooting steps:

Note: Be sure to restart your browser (close and re-open a new browser window) and re-run the System Test after completing each of these step to determine if is Java is functioning. Simply re-loading the page will not provide updated results.

Step 1. Download the latest version of JAVA

Download the latest JAVA version Use the appropriate link below. After saving the file, you must double click on the file to start the installation process. After installation is complete, re-start your system and open a new browser window to test it.

Java for PC
Java for Mac (OS 10.4 to 10.6) - Use the Software Update feature (on the Apple menu) to check that you have the most up-to-date version of Java for your Mac.
Java for Mac (OS 10.7) With this particular OS, Java is no longer installed by default as part of the OS, you will need to download it using the link provided here.

STEP 2. Check that Java is enabled within your Operating System


a. From the Start menu, select Settings, then Control Panel.
b. Double-click to open Java Control Panel.
c. Click the Advanced tab.
d. Click on + icon next to Default Java for browsers.
e. Make sure the box next to Internet Explorer or Mozilla is checked.
f. If it is not checked, click the checkbox to enable Java for your Web browser.
g. Click Apply.


a. From Finder, click on the Go Menu and select Utilities.
b. Double click on the Java Preferences icon.
c. On the General tab, check Enable applet plug-in and Web Start applications
d. Close Java Preferences and restart your browser.

STEP 3. Check that Java is enabled within your Browser

(locate specific browser below)

Internet Explorer 8 or 9 for Windows

a. On the Internet Explorer top menu, click Tools, click Manage Add-Ons
b. Click Toolbars and Extensions
c. Under the "Sun Microsystems, Inc." section, make sure all of the items within this section are Enabled.
Note: If nothing is shown within the Sun Microsystems section, or it does not appear in the Add-ons area, it means that Java is not installed.

Firefox for Windows

a. From the Firefox or Tools menu, select Add-ons
b. Select the Plugins panel.
c. Click on the Java item to select it.
d. Click Enable. (If it shows Disable, it means Java is already enabled.)

Chrome for Windows

a. Type: about:plugins in the address bar.
b. From the list of plugins, verify the Java Plug-in is enabled.

Safari for Mac

a. From the Safari menu. select the Preferences option.
b. In the top window, click on the Security option.
c. Under the Web Content area, make sure the "Enable Java" checkbox is selected.
d. Close the window.

Firefox for Mac:

a. From the Firefox top menu, click Preferences, then click Content
b. Place checkmark next to "Enable Java" setting.
c. Close the window.

STEP 4. Check for/Remove multiple or older versions of Java


a. Click Start, click Control Panel
b. Double click the Add/Remove Programs control panel icon.
c. This will display a list of software on your system, scroll down to the "Java" section.
d. If multiple versions of Java are listed, uninstall all of them. (Do not remove anything besides Java)
e. Install the latest version of Java from:

STEP 5. Clear the Java Cache

(Follow the steps shown below)

Windows Users -Clearing Java Cache

a. From the Windows Start button, click Settings, click Control Panel.
b. Double-click Java icon to open the Java Control Panel
c. Under the Temporary Internet Files section, click the Settings button.
d. On the next screen, click the Delete Files button, make sure Applications & Applets is checked and click OK.
e. Continue to click OK, until you exit from the Control Panel.
f. Restart (close and re-open) your browser.

Mac Users - Clearing Java Cache

a. Open Finder.
b. Go to Applications.
c. Find the Utilities folder.
d. Find the Java folder and go to J2SE folder, where you will find Java Preferences. Open this file.
e. When the Java Preferences window opens, select Delete Files under the General tab.
f. When the Delete Temporary Files window opens, make sure all boxes are checked. Select OK.

Additional Notes:
The ZoneAlarm Pro software firewall can block Java.
The NoScript extension for Firefox will block Java.
The Adblock extension for Firefox can cause Java to stop working if OBJ-TABS are enabled.
If Java version "1.6.0_03" is installed on Vista w/Firefox, there is a known bug which will prevent the Java Plug-in from loading. Update Java to the latest version to resolve this issue.


More Information 

General Campus Information

University of California, Riverside
900 University Ave.
Riverside, CA 92521
Tel: (951) 827-1012

Department Information

Computing & Communications
Computing & Communications Bldg.

Tel: (951) 827-4741
Fax: (951) 827-4541