Oracle Database 11g Failing to mount on windows server 2012

Question

I have an Oracle 11g database installed on Windows Server 2012. It's failing to mount after shutdown. The reason why i want to mount it is that i want to enable Archive log mode, and i have been able to do the basic steps of Enabling Archive Log Mode on Linux but the same steps are failing on mount stage:

Below are the steps i have done:

1. SHUTDOWN IMMEDIATE

2. startup mount

   It is here where the error below pops up:

ORA-12505: TNS:listener does not currently know of SID given in connect descriptor

PS C:\Users\inhousedwh> sqlplus 
SQL*Plus: Release 11.2.0.1.0 Production on Thu Oct 17 17:46:02 2019 
Copyright (c) 1982, 2010, Oracle. All rights reserved. 
Enter user-name: sys@rvas as sysdba 
Enter password: 
Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production With the Partitioning, OLAP, Data Mining and Real Application Testing options 
SQL> shutdown immediate; 
Database closed. 
Database dismounted. 
ORACLE instance shut down. 
SQL> startup mount 
ORA-12505: TNS:listener does not currently know of SID given in connect descriptor

Answer 1

Use a local connection.

sqlplus sys as sysdba

or

sqlplus / as sysdba

In your output, you used a remote connection. Database instances can be started through remote connections only if you have registered them in the listener manually with static registration.