This could be known and primitive to many people, however i am putting it to help the community in general from different technical-levels.
when you initiate sqlplus and trying to connect to your database instance you face the following error:
ORA-12560: TNS:protocol adapter error
if you are using windows OS, you need to check the following:
- check that the database services is up and running, go to the search icon and search for “services” and ensure all Oracle services are up and running.
- if Oracle database is up and running fine, then check your environment variables in CMD, you need to set the following:
set ORACLE_SID= ORACLE33
to check that its reflected, execute the following to verify the value of ORACLE_HOME:
now try initiating sqlplus and it will be working 🙂