Why is FKM displaying this message on a Windows server: "WARNING: Being used exclusively by another process"

This warning message is created by FKM based on the ERROR_SHARING_VIOLATION error from Windows. This happens when FKM tries to access a file but fails to display fail attributes due to the exclusive hold of outside process code.

From the Prerequisites section of the FKM Plugin User Guide: The Netprobe user must have a read-access permission to the monitored file. Installing the Microsoft Process Explorer application may help to identify which process is holding the file.