If i try to log on to my Oracle database using either the command line or SQL*Plus or through an application I've written, I get the following error messages:
ORA-01034 ORACLE not available, ORACLE database is not started ORA-27101: shared memory realm does not exist.
I've never experienced this before. I am running Oracle 9i on a stand-alone Windows 2000 Professional machine. I just came to work one day and saw this. I wrote a script to start oracle manually, which works fine but I don't want to have to run a script each time, especially now that I've hooked the system to the network. People should be able to start the system and start accesing Oracle right away without having to first run a script. Can you help?
There are two reasons why you would get the ORA-1034 error. Either your database is not started, or your environment is configured incorrectly. Since you are on Windows and you didn't have this problem before, I would suspect that your database is not up and running.
The first thing I'd check is your service. Go to Control Panel->Administrative Tools->Services and look for a service titled OracleSIDService (where SID your database identifier). Make sure the service is started. Also ensure that the service is set to Automatically restart on server reboot. If that all checks out, then it is likely that your service is trying to start the database, but some sort of failure occurs. Consult your database's Alert Log to find out why the database is not starting.