Update fails to install BITS 2.0 and WinHTTP 5.1 (KB842773)

Hello,
Any assistance would be greatly appreciated. I recently have tried system
restore (both through Windows XP and through my HP system restore). However,
when I try to run Microsoft Update, the initial set of updates fails to
install, in particular the following: Update for Background Intelligent
Transfer Service (BITS) 2.0 and WinHTTP 5.1 (KB842773).

I have tried this several times to no avail. As a result, I can install no
subsequent updates, and my PC is stuck with 2005 software.

I have tried all that theses two Microsoft websites offer that were
possible. I did have some problems, though.

For, http://support.microsoft.com/kb/916251 , I was unable to delete the
%allusersprofile%\Application Data\Microsoft\Network\Downloader folder
because I could not locate it on my system.

Also, under Services, my SITS Startup was already set as "started". Changing
it to Automatic had no effect.

Further, for the Workaround option, I could not remove Windows XP Hotfix -
KB842773, under Currently installed programs because it was not listed as a
curret program.

I also tried all of the tips in http://support.microsoft.com/kb/822798 save
for performing an in place upgrade.

I still am getting the following message when I run Windows Update, and no
subsequent updates can be installed.

Some updates could not be installed. The following updates were not
installed: Update for Background Intelligent Transfer Service (BITS) 2.0 and
WinHTTP 5.1 (KB842773).

Please help if you can. Thanks again,
andrew