How to fix the Oracle error ORA-12558: TNS:protocol adapter not loaded?

In this post, you’ll learn more about the Oracle ErrorORA-12558: TNS:protocol adapter not loaded with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

ORA-12558: TNS:protocol adapter not loaded

Reason for the Error ORA-12558: TNS:protocol adapter not loaded

On some platforms (such as OS/2) protocol adapters are loaded at run-time. If the shared library (or DLL) for the protocol adapter has not been loaded, then this error is returned.

How to fix the Error ORA-12558: TNS:protocol adapter not loaded ?

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

For further details, turn on tracing and reexecute the operation. The trace file will have the name of the shared library (or DLL) that has not been loaded.