Can't download the Service Pack-Windows thinks I have pirated software!

[James Stewart]

I've got an EOM version of Windows XP. When I first
installed it on my new PC about 3 years ago, it worked
fine. When I reinstalled about a year and a half ago, it
worked fine. When I reinstalled this weekend, it worked
fine.
But yesterday, when I went to the Windows Update site and
attempted to download the Service Pack, it eventually told
me it could not finish the download because "The Product
Key used to install Windows is invalid. Please contact
your system administrator or retailer immediately to
obtain a valid Product Key."
I've used Windows Update many times, downloading patches,
new software, updates. Never a problem.
I tried to send a message to (e-mail address removed) and got
a useless form letter that told me "it is not possible for
us to provide feedback actions taken on your submission."
What is it that is 'invalid'? How to I correct this?

 

[Pavel A.]

Since you got an OEM version, you can't call MS product suport,
but maybe you can use Windows Update only online support.

In Win. update menu click "help and support" then click
"Request technical support for only Windows Update service issues from Microsoft Product Support (requires an Online
Profile)."

--PA