Read this recent discussion.

by R. Proffitt Moderator - 3/23/13 9:57 AM

In Reply to: Cannot install java version 7 update 17 by mrblueeyes

http://forums.cnet.com/7723-6122_102-589066/why-can-t-i-get-wu-kkb2814124/?tag=contentBody;threadListing

Yes, it was NOT about JAVA. But it is a similar error and the tools noted as well as JAVARA (see google) are the usual cure.
Bob