ORA-12560: TNS:protocol adaptor error

This is the common error in oracle database related to oracle database connection

Problem Statement

ORA-12560: TNS:protocol adaptor error

Solutions

1. Check if your database is up and running
2. Make sure listener is up and running
3. Crosscheck if your ORACLE_HOME and ORACLE_SID set up properly
4. if you are using windows server then go to services.msc and look for oracle service of database. service needs to be started.
5. Also check for firewall issue

#ORA-12560