In this post, you’ll learn more about the Oracle ErrorTNS-01203: Missing the account (string) specified by DEFAULT_USER_ACCOUNT in SID_DESC with the details on why you receive this error and the possible solution to fix it.
Oracle Error Description
TNS-01203: Missing the account (string) specified by DEFAULT_USER_ACCOUNT in SID_DESC
Reason for the Error TNS-01203: Missing the account (string) specified by DEFAULT_USER_ACCOUNT in SID_DESC
Cause: The unprivileged OS account is missing from /etc/passwd.
How to fix the Error TNS-01203: Missing the account (string) specified by DEFAULT_USER_ACCOUNT in SID_DESC ?
You can fix this error in Oracle by following the below steps
Action: Check the DEFAULT_USER_ACCOUNT parameter in the SID_DESC in LISTENER.ORA and verify it has a valid entry in /etc/passwd. This is the account that the Oracle shadow process will be started with if the the connecting client has database privileges or does not exist on this machine.