At least two kinds of applications use the Java plugin of the web browser:
Let's see some questions & answers regarding applications that run on the browser using the Java plugin.
The real problem can be any of the following:
- Java has been installed on the client machine
- Java has been updated on the client machine. If it's outdated, it can be blocked by the browser.
If Java is already installed on the client, but applets do not work, you may need to check if Java is enabled.
To see whether your browser is configured to use Java, check your settings in the Java Control Panel.
- In the Java Control Panel, click the Security tab.
- Select the option Enable Java content in the browser.
- Click Apply and then OK to confirm the changes.
- Restart the browser to enable the changes.
Consider How do I control when an untrusted applet or application runs in my web browser?
Because the implementation is based on an applet, this dialog always appears the first time the application runs.
Do you want to run this application?
The user should check "Do not show this again for apps from the publisher and location above", and confirm to Run the application.
Allow access to the following application from this website?
The user should check "Do not show this again for this app and website" and click the Allow button. Otherwise, the application will not run until a new instance of the browser is opened, and the user is asked again.
This dialog cannot be avoided as from Java 1.7_055 unless some steps are followed. See How to prevent the Security Warning with Java for more information.
The applet is cached in the client machine, depending on the client settings.
See this link in order to clear the java memory cache.
How do I enable Java through the Control Panel?
How do I enable Java in my web browser?
How can I run or activate Java in the browser?