I have a single 10.2.0.5 database running on Windows 2008 R2 and everything seems to be good, minus the OEM. I originally had the OEM running too, but on the homepage, after signing on the database, there was a java exception. The fact there was a java exception didn't seem to limit the functionality of the OEM, but I thought I'd investigate how to get rid of the java exception that was displaying. I wish I would have saved the exact java exception description, but I didn't. I do remember that within the error description I saw my Windows "Computer Name" and Windows "Full Computer Name". That led me to believe I could change a hostname setting somewhere that would get rid of this java exception.
So I started tinkering with the environment variable ORACLE_HOSTNAME, the HOST within tnsnames.ora, and the HOST within listener.ora, trying different combinations of IP address, Windows Computer Name, and Full Computer Name, thinking I could reconfigure the OEM using emca after trying different combinations and fix the original java exception problem.
To get to the point: The DB is up, the listener is up, I don't really care about the original java exception right now, I'm just trying to get the OEM up and running again.
I've went through numerous iterations of emca commands and it always freezes at :
INFO: Starting Database Control (this may take a while) ... Apr 18, 2013 10:38:52 AM oracle.sysman.emcp.EMConfig perform SEVERE: Error starting Database Control
At this point I just want to get the OEM running. Is there a way I can clear all the previous OEM settings and just configure it anew and get it running?