The Administration Console provides an interface for administrative functions. If the Administration Console is not accessible, it might be for one of several reasons.
The server must be running before the Administration Console can be accessed.
Review the information in Did the Server Start? to determine if the server is running.
The default port number for the EE and SE Administration Console is 4849; for the PE Administration Console it is 4848. Also note that the URL for the EE and SE console requires secure HTTP (https://servername:4849.), whereas the PE console uses standard HTTP (http://servername:4848). However, it could be running on a different port number than expected, either because it was intentionally installed there, or because that port was taken when the server was started.
Refer to Was the Server Started at the Expected Port? for guidelines on verifying the port on which the Administration Console is running, and be sure to enter the correct port number and HTTP protocol when invoking the Administration Console.
According to the J2EE 1.4 Specification, the Security Manager is not optional; it must be enabled in the Application Server. Since there is no configuration interface in the Application Server for disabling the Security Manager, it can only be disabled by directly modifying the domain.xml configuration file in such a way that the following line is removed:
The -Djava.security.policy=yourPolicy option must be present in the domain.xml file to access the Administration Console.