You should only worry if:
Since gpcl6win64.exe is not a standalone Microsoft component, you should identify which software installed it.
If the file worked previously but errors started after a recent Windows update or software installation:
If you find this file running on your PC, it likely installed alongside one of the following applications:
Download the latest Ghostscript release from https://www.ghostscript.com/ (or Artifex). Run the installer—it automatically replaces older executables.