I was using Microsoft's Windows LIve OneCare anti-virus software on two of my computers - then MS decided not to continue with this product - so it expired - after sunday July 11 2010 - many services on my computers stopped working.

no printers
couldn't rename a file
windows mail wouldn't start

Uninstall wouldn't work

how to fix it? 

restart your computer - hold down F2 key - go into setup and change the date to before July 11th 2010
start computer and then you can uninstall the piece of crap known as windows live onecare.
restart and go into setup and set date back

I got Norton 360 - to install it on the second computer is easy - go to the Symantec site and on the left near the bottom
is fulfill my order - sign in a and you will seed your order and there is a place to click in the middle of the invoice looking thing
to start the download!! Great!

All done!