In this post, you’ll learn more about the Oracle ErrorORA-12665: NLS string open failed with the details on why you receive this error and the possible solution to fix it.
Oracle Error Description
ORA-12665: NLS string open failed
Reason for the Error ORA-12665: NLS string open failed
A native service was unable to make a string available for use by the National Language Support component.
How to fix the Error ORA-12665: NLS string open failed ?
You can fix this error in Oracle by following the below steps
Make sure the National Language Support component has been properly. If it has, enable tracing and report the problem to Customer Support.