I have an instance that will not startup if I attempt to start it in oem. Also I cannot log as sys using sqlplus, I get the same message.
However, if I stop and restart the service in control panel it restarts ok (even though the service is pointing to the same pfile as I tried to use from oem to start it up)
I have previously created spfile from pfile. My Pfile entry points to the spfile now and that is all. Could this be that the spfile creation did not work properly? - althoguh, if this was the case then the service could not restart using it either?

The tnsnames.ora file looks fine.
The server is all ok as there are other instances on it that work ok.

Also, silly questino, but where do I identify in oem whee it will look for the initialisation file on startup - cannot see it in there, but I'm sure it is there somewhere, and I could change it.
Actually, could this be the problem? - it is trying to use the def_instancename file from sysman/config I would imagine, until I tell it to use something else?