Caused by: oracle.net.ns.NetException: The Network Adapter could not establish the connection
This issue is caused due to "OracleOraDB18Home1TNSListener" service is not running, to start this service, please follow below steps:
1.Navigate to following location admin directory present in the oracle installation folder e.g. C:\app\Administrator\product\21c\homes\OraDB21Home1\network\admin
2.Open listener.ora and update host value to "localhost"
3.Save the file with the latest changes.
4.Now, open tnsnames.ora file and update host value to "localhost".
5.Save the changes.
6.Restart the machine.
7.Open service manager and ensure "OracleOraDB18Home1TNSListener" service is running after system restart.
@snimbalkar I was facing the same issue and have been searching for a solution for a day. It worked for me! Thank you very much 🙂