When I am running XP via Bootcamp on my Macbook I get the little yellow shield telling me there is a windows update. It's service pack 3 for XP. When I run the update to try to install service pack 3 it fails to install telling me there is not enough space that the service pack needs at least 4 MB. My XP partition is 30GB and 21 GB are free. Why does the update think there is not enough space?