1- unplug CA from network.
If your CA is accessible via a network you sure not be running a trusted CA.
OTOH, installing XP was easy, everything on the laptop works, she has OFFICE (which all her friends have, and makes it VERY easy. Instead of hearing "lucy does it this way, why doesn't my computer work that way", I now hear "This is great. I have the same thing as Lucy, and when I had a problem last night, I could call her instead of you!!!".
I call shenanigans on this. I know my grandmother doesn't use an office productivity suite. I doubt many others do, as the Microsoft office cost $$$$, and it would only confuse them. What are they doing, sending bingo announcements in PPT. Anyways, just give them a gmail account. It will let them view office docs as html. Problem solved.