How to start Enterprise Manager(em) console in Oracle AS 10.1.3.4 in windows and linux

I have installed Oracle AS 10.1.3.1 and then applied patch to upgrade it to 10.1.3.4

This OAS is configured to listen at port 80.

When I go to http://localhost after starting OPMN, i can wee the welcome screen.

But now I want to login to Enterprise Manager(em) console so I go to http://localhost/em but this link doesn't work and says:

Not Found The requested URL /em was

not found on this server.

Please tell me how to start em console in OAS 10.1.3.4

Firstly to verify what port you should be using (and providing you haven't reconfigured it) you can check the file:

portlist.ini

which can be found at

ORACLE_APPLICATION_SERVER_HOME\install

Once you are sure that you are using the correct port, have you started the console? (opmnctl start all command doesn't start the AS control) You can try starting it using the following command:

ORACLE_APPLICATION_SERVER_HOME\opmn\bin\opmnctl startproc application=ascontrol