I have modified HHUPD.EXE INF to install all files no matter which other versions [even newer] you might have.
If you happen to have a newer version, it is from one of the 2000/XP/2003 updates, but you should have the files from HHUPD.EXE, because they are meant specifically for Win9x/ME OSes.
I have also added a "finished install" message:
"Install completed. You must reboot for this Update to take effect."
Your computer will reboot when you click the OK button.
IMHO:
Personally, I like it better when it reboots automatically without any extra prompts/dialog boxes to click.
The text which appears when you first start HHUPD.EXE now lists all files that will be installed [when you click the Yes button] with locations and version builds.
So please download the updated file [710 KB, English]:
http://www.mdgx.com/files/HHUPD.EXE
and try it out.
HTH