How to fix the Oracle error TNS-00042: INTCTL: CMANAGER already running. Start operation cancelled?

In this post, you’ll learn more about the Oracle ErrorTNS-00042: INTCTL: CMANAGER already running. Start operation cancelled with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

TNS-00042: INTCTL: CMANAGER already running. Start operation cancelled

Reason for the Error TNS-00042: INTCTL: CMANAGER already running. Start operation cancelled

Cause: There is a Connection Manager already running and listening on the same addresses.

How to fix the Error TNS-00042: INTCTL: CMANAGER already running. Start operation cancelled ?

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

Action: None; the Connection Manager is already running.