Hi, khdphd, and welcome to the forum....
They say they cannot download the file? I have always seen every HP that uses those hkCMD.exe files to be able to download them for that computer in the event of a reinstall.
Did you look at software available for download for your computer? If it is there, then you can download it, uninstall the current version, reboot and install that one and it should load the original files back in place.
Try uninstalling hkcmnd from Programs and Features (it may be named something a bit more fancy)
And I know what HP *said* - but look anyway.