When attempting to access a database using Personal Oracle 8i, an error was encountered. Either an ORA-12541: TNS:no listener, OR similar errors.
By default the Oracle Listener is not started in Personal Oracle.
To check if the Oracle Listener is started, go to the Command Prompt and type C:\>LSNRCTL and the return key. Type Status, and then the return key. You will get the status of the Listener returned to you. If the Listener is not started, than while still in the command prompt, type start. This will start your listener.
You can verify this by typing Status at the command Prompt again.