It happens more than you would think, Wendy.
As an Intro to Windows instructor, I've now included the answer to that question in any Windows curriculum I write, along with the strong suggestion to NOT use the CD/DVD drive as a cup holder.
Then you'll both be familiar with PEBKAC = problem exists between keyboard and chair.
More here http://pebkac.ubergoth.net/luser/
When 911 was introduced as the US emergency number, it was known as
nine-eleven, but so many people couldn't work out where the eleven hole
was on a rotary telephone dial, that they changed it to nine-one-one.
--
Tim Morrison
C-Tech volunteer