In the Java Control Panel, click on the Java tab. Verify that the latest Java Runtime version is enabled by checking the Enabled box . Click OK in Java Control Panel window to confirm changes and close the window. Try to run same applet and verify it is now running using latest version of Java installed in your system.
Read moreHow do I check if Java is installed?
Going to a command line and typing java -version can tell us for sure if Java is installed.
Read moreHow do I check Java version manually?
Q: How can I tell if Java Runtime Environment is installed on my Windows machine?
Read moreDo I have Java Ubuntu?
By default, Ubuntu does not come with Java (or the Java Runtime Environment, JRE) installed. However, you may need it for some programs or games like Minecraft.
Read moreHow do I change Java version in Ubuntu?
How do I switch Java on Ubuntu?
Read moreHow do I verify Java version?
Java Version under Windows Start Menu – Java 7 Update 40 (7u40) and later versions
Read moreHow do I install Java 1.8 on Mac?
Installing Java 8
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