It seems Microsoft just can’t get this one right.
Installing some old legacy apps that use Winhlp32 for their help leads you on an out of the box install of Windows 8 to this page:Windows Help program (WinHlp32.exe) for Windows 8, which is KB917607
Unfortunately, installing this update doesn’t actually help on a 64 bit system.
When you do try to launch the installed winhelp, you get a partial title bar describing the problem.
Digging out Spy++ reveals that the actual title continues:
“located in the System directory.”
Moving the file there unfortunately, doesn’t actually help.
So, for the moment, I’m uninstalling by running the downloaded msu file from the update from an elevated command prompt like this:
Attempting to install the Windows8-RT-KB917607-x86.msu on either a 32 bit or a 64 bit system claims that “this update isn’t applicable to your computer”