missing proxycfg.exe and winhttps.dll

I have been unable to use the Windows Update Site ever since installing the
latest Automatic Updater. When I try to get updates I get as far as the page
"Checking for the latest updates..." and not further and I am getting errors
in the WindowsUpdater.log. I found several threads that seems to describe my
problem but when I tried to run the ProxyCfd.exe too This is not found. I
obtained a copy of the tool from another PC and not is complains that
winhttps.dll is not found. I am running Windows 2000 Pro with SP4 installed
and up until about two weeks ago I was up to date on all available updates.

It would appear I am missing Windows HTTP Services but this was supposed to
be installed with SP3 and SP4. To my knowledge I have not installed
Microsoft XML SP4. Like I said this all started with the install of the new
Microsoft Updater. Can somebody tell me or provide a link to where I can
obtain Windows HTTP Services 5.1 or suggest some alternative course of action.

I do not know if this is related but many (not all) of the icons for
programs listed in the "Add/Remove Program" tool of the control panel are
also missing and this also happened at the same time.

Thank you in advance
David