What is exact cause of "No message file for product=RDBMS"

My oracle_home is set correctly.

Last think yesterday I installed 10G client on my (windows xp)workstation for testing, putting it in a new oracle home etc. now this morning I can't connect to the local 9i db and I'm not sure why. I took the new 10G home out of the path so my sqlplus starts properly, put the oracle_home back to the 9i home (it was now blank after the 10g clinet install) and oracle_sid is set to local db sid as always. Whenever I try to connect to the local db I am now getting error messages along with the "No message file for product=RDBMS facility=ORA". One of the messages is 01031 (insufficient priveleges) and I have no idea why as I'm using the "connect sys/pass as sysdba" like I always do to connect to the idle instance and start it up (we had a power outage and all workstations rebooted)

The 10G client install did something that caused everything to go south, but I'm stymied at what exactly is causing me not to be able to connect. I can connect to remote db's ok, just not the local one. (For some reason on this machine only the service auto starts, not the database so I always log in as sysdba and issue a startup command.) Received on Tue Apr 24 2007 - 09:18:25 CDT