Quote Originally Posted by dontinou View Post
SQL> conn / as sysdba
Connected to an idle instance.
SQL> startup
ORACLE instance started.

Total System Global Area 612368384 bytes
Fixed Size 1304752 bytes
Variable Size 171968336 bytes
Database Buffers 436207616 bytes
Redo Buffers 2887680 bytes
Database mounted.
ORA-01092: ORACLE instance terminated. Disconnection forced


SQL>

What should I try next? How come I have to manually start the instance? Do I have to do this every time? Why is it terminating?

Also, nothing in the Application Event Log that tells me why I got the ORA-01092, is there a logfile somewhere?
Did you check alert log?