ArcIMS J2SE JRE configuration
Java Viewers require a system-registered Java 2 Platform Standard Edition Java Runtime Environment (J2SE JRE) version 1.6.0_16 or higher. A J2SE JRE does not have to be installed prior to installing ArcIMS; the postinstallation setup provides you with the opportunity to install and configure a system registered J2SE JRE 1.6.0_16.
ArcIMS Author, Designer, and Administrator use a private J2SE JRE by default. A system registered J2SE JRE can be used for these applications.

J2SE JRE is not needed if J2SE SDK 1.6.0_16 or higher is installed on the computer.
Configure system J2SE JRE

A system registered J2SE JRE is required for the Java Viewers. If J2SE JRE version 1.6.0_16 or higher is not detected on your machine, you will be provided with this opportunity to either install J2SE JRE 1.6.0_16 or browse to an existing system registered J2SE JRE.
ArcIMS Author, Designer, and Administrator, by default, do not use the system-registered J2SE JRE. ArcIMS Author, Designer, and Administrator use J2SE JRE files installed in the ArcIMS Installation Directory. This is referred to as a private JRE. Private JREs are not registered and are only available to the application that copied the files to disk. Therefore, the private JRE cannot be used for the Java Viewers. The check box provided on this dialog box should only be checked if you want to apply your system J2SE JRE to ArcIMS Author, Designer, and Administrator (instead of using the private JRE)—this is not recommended.

- The private JRE is always installed.
- If you checked the box to apply the system-registered J2SE JRE to ArcIMS Author, Designer, and Administrator, and they are failing to open, run through this option in the postinstallation again and uncheck the box on this dialog box.