Java WebStart fails on Mac OS Mountain Lion

After searching several hours for a helpful hint on support pages and FAQs that really (!) work this question:

I need Java WebStart for an application that works on MAC OS X (Mountain) Lion. So far we had no problem with the application on Snow Leopard.

On my MacBookAir the applications starts. On a second system with the same OS and the same Java installations I always receive the well known error window (with the corresponding English message like "you have to load the Java Runtime Environment for Web Start...)

A click on "more information" delivers the java.com web page that offers the JRE download that is already installed.

The corresponding console error message is:

"No Java Web components present, requesting install"

System: Mac OS X 10.8.2, Intel Core Duo

Installed Java:

  • Apple 1.6.0_37-b06-434
  • Oracle Java SE Run Time environment:7u9)
  • Oracle Java SE jdk-7u9-macosx-x64.dmg)

Output of /usr/bin/java -version is: Java SE runtime environment 1.7.0_09-b05

The java.com website signals on the installed version web page): Version7 Update 9 installed.

The Java Control Panel also says:

"Version 7 Update 9 installed"

The Java Control Panel offers no choice to "enable the Java web start".

Any suggestion is very welcome!

Best regards, Werner


The oracle java version here (1.7.0_09-b05) is old and is blocked by Safari as a security risk a see this Apple note. Upgrade to the current JDK which is currently Java SE 7u21.