An error “you need to install the legacy Java SE 6 runtime”, is encountered when you open any Adobe application.
With Mac OS 10.7 (Lion) and later, the Java runtime is no longer installed automatically as part of the OS installation. Follow any of the methods below to install Java runtime.
You can download and install the latest Java runtime from the Java website - Download Free Java Software.
On Mac OS 10.10 (Yosemite), when you launch any Adobe product, you might receive a warning "The Application has been moved and its path has been changed...".
Click Repair Now or Update button to update the location and resolve the issue. When prompted for password , enter your system password to complete.
If Java runtime is not installed, you are prompted to install when you first launch any Adobe product. Follow the onscreen instructions in the Java required notification dialog box to install.
Use the following method to initiate the Java runtime installation or confirm if it is installed.
If Java is not installed, you receive the following message: “To open “Java Preferences," you need a Java runtime. Would you like to install one now?”
Many Adobe applications depend on the Oracle Java Runtime Environment (JRE) for some features to work. Apple recently changed the way it includes Java in Mac OS, and with Lion, Java is no longer preinstalled. It is now an optional install that you must select.
Since current Adobe installers and applications were built before these changes by Apple, Adobe software anticipates that Java is installed. Adobe and Apple have worked together to ensure that you can install Java at OS install time. Or it can be installed later before you install Adobe applications. At runtime, when you launch an Adobe application, you are prompted to install Java if it is not already installed. If you do not install Java before running an Adobe application, there can be missing or improperly behaving features. If you encounter any issues, install Java to correct the problems. Adobe recommends that corporate IT organizations pre install Java (or make sure that Java can be installed through their firewalls/security) to avoid conflicts with Adobe applications.
If the Java runtime is not installed, some issues that are known to occur include -