Oracle - Unable to access admin console for local database

Summary: I set up my laptop as a development system to work on a JSP application which connects to an Oracle 10g database. I had installed Oracle locally on my laptop a few times and finally got a stable version up and running, although I still run into issues here and there. One of the problems I was experiencing recently was being unable to open the administration page for a local database I created. It was only happening intermittently and seemed to be related to having multiple network interfaces enabled. If I disabled all of the interfaces I wasn't using, and left only the one I needed, then it would usually work. However, this poses a problem when I must have more than one interface enabled, such as when connected to another network via a VPN. After much research, I found quite a bit of information about this problem. Seems it is rather common.

Resolution: Most times, the fix for the problem is to install and configure the Microsoft Loopback Adapter. Also, the local hosts file may need to be modified. Details on how to do this can be found easily on the web by doing a quick search for "installing microsoft loopback adapter". Also, if you throw an "oracle" in the search somewhere, you'll find a lot of info related to this specific issue. Here's someone else who was experiencing a similar problem. http://oracleplz.blogspot.com/2006/02/10g-installation-on-windows.html

You may need to verify that the admin port is listening as well. You can test this by running telnet from the command line. For instance, telnet computername 5500. If the connection fails, run a netstat -a command and make sure that the computer is listening on the specfied port. If the system is not listening on the port, then the service is probably not started. To manually start the database service, open up the service list in Windows and make sure that the OracleDBConsole service is started. If it's unable to start, you may need to manually restart the OracleService service.