The Java platform was one of the first systems to offer support for the execution of code from remote sources. An applet can run in the browser of a user, executing code downloaded from a server HTTP . The code of an applet running in a very restrictive area, which protects the user from erroneous or malicious codes. This area is bounded by an object called a security manager. Such an object exists for the local code, but then it is inactive by default. The security manager (SecurityManager Class) to define a number of authorizations to use local system resources (file system, network, system properties, ...). Permission sets - accessor code (typically an applet - possibly signed - sent from a web server); - a local resource concern (eg a directory); - a set of rights (eg read / write). Publishers applet may request a certificate to enable them to digitally sign an applet to be safe, potentially giving them (with proper authorization) permission to leave the area and restricted access resources on the local system. windsman.
thank you but I still have question, when I format my computer will certificate change? because they block my certificate.
If you format your computer, all certificates are erased, if you reinstall java environnement, you will have to allow or deny again all websites that work with java. windsman.
I reinstall Java but the seem, after that I install windows XP by VMware and have tried again and it's work fine now so, do you think they block mac address or not because it is working on VMware.
No, but now I'm working with website by VMware I can't format my Pc it will take long time to set all setting and move files so if you have another solution I will try it.