How to fix the Oracle error PCC-02104: Unable to connect to Oracle?

In this post, you’ll learn more about the Oracle ErrorPCC-02104: Unable to connect to Oracle with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

PCC-02104: Unable to connect to Oracle

Reason for the Error PCC-02104: Unable to connect to Oracle

Cause: The precompiler could not connect to Oracle with the username, password, and, if applicable, database link that was supplied. Note that this is a precompiler message, not a runtime message. This means that the USERID option value, either on the command line or in a configuration file, was incorrect.

How to fix the Error PCC-02104: Unable to connect to Oracle ?

You can fix this error in Oracle by following the below steps

Action: Check that the username and password are current and correct. Run SQL*DBA or SQL*PLUS and verify that connection can be made using that username and password.