I know there similar questions on how to enable the Java 7 JRE on Mountain Lion when Apple's Java 6 JRE is installed as well.

But I just did a clean install of Mountain Lion, installed Java 7 JRE - not Java 7 JDK - and it is not being detected.

I see the Java icon in System Preferences. But Java applications are still prompting for a Java 6 installation from Mountain Lion. And running "java -version" from the command line also does the same.

Oracle's instructions seem to say that I do not need to do anything further then simply installing the JRE. And online tutorials I read also suggest the same.

Does anyone have an idea why this is?

  • Good question! I just faced the same issue with a fresh Lion + JRE7. Thanks! +1
    – jweyrich
    Commented Jan 17, 2013 at 19:58

2 Answers 2


In Oracle's JRE 7 for Mac installation instructions, it states:

Installing a JRE from Oracle will not:

  • Update java -version symlinks or add java to your path.

  • Show the installed JRE in the Java Preferences.app

To be able to do the above, you need to install the JDK.

After installing the JDK, go to Applications > Utilities > Java Preferences.app and drag Java SE 7 to the top to indicate that it is preferred. You may also switch off Java SE 6 entirely without uninstalling it.

  • 2
    Unbelievable that I missed that! I installed JDK and it worked. Thank you so much for your help.
    – 9ee1
    Commented Sep 29, 2012 at 7:02

Uninstall java by revo and go to control panal and java and settings and deleted files. then click ok.and restart computer then install java again from java.com

  • Java is not installed (well /usr/bin/java) is not - the one the OP installed is just for Java applets
    – mmmmmm
    Commented May 2, 2013 at 21:44

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .