OBIEE 12c: When running analysis/report throwing error ORA-12541: TNS:no listener at OCI call OCIServerAttach. (HY000):

Error:

View Display Error
Odbc driver returned an error (SQLExecDirectW).
Error Details
Error Codes: OPR4ONWY:U9IM8TAC:U9IM8TAC:U9IM8TAC:U9IM8TAC:OI2DL65P
State: HY000. Code: 10058. [NQODBC] [SQL_STATE: HY000] [nQSError: 10058] A
general error has occurred. (HY000)
State: HY000. Code: 43113. [nQSError: 43113] Message returned from OBIS. (HY000)
State: HY000. Code: 17001. [nQSError: 17001] Oracle Error code: 12541, message: ORA-
12541: TNS:no listener at OCI call OCIServerAttach. (HY000)
State: HY000. Code: 17014. [nQSError: 17014] Could not connect to Oracle database.
(HY000)

Solution:

Step 1: Open the current RPD file using Admin tool and check the connection pool entries are correct.
Step 2: Ensure tnsnames file in the bi home is the correct one for OBIEE

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