Just looked it up and the dog was named "Rover" (another classy name from Microsoft). Rover was an option when introduced in "Microsoft Bob", but then later became the default search companion in XP's file search.

Also, we have Rover to blame for Comic Sans:

> Microsoft graphic designer Vincent Connare designed the typeface Comic Sans when he noticed that Rover's speech was displayed in Times New Roman, which he felt was inappropriate for a cartoon dog.