Since December 3, Windows Update apparently hasn't been working on Win7
machines--something about a date that was allowed to expire. My computer
was affected. Last night, a website I follow for computer news said the
problem had been fixed by Microsoft and no work-arounds were needed.

The problem was NOT fixed on my computer.

I went back to the site and read all the Comments about this issue. One
simple suggestion worked for me. Go into Windows Update | Change
Settings, and change from (in my case) "Check for updates but let me
choose when to download and install them" to "Never check for updates."
Then click OK. After that, go back and change the settings back to what
you had. That apparently resets the expiration date.

Or at least it worked for me...

--
Jo-Anne