Both my sound device and networking device on Windows XP suddenly stopped working this weekend, and I have tried all types of ways, including using 'system restore point', updating drivers, adding windows components to no avail. However, I used this morning a 'live linux cd' (one of many available for linux distributions on http://distrowatch.com/)
and under linux both the sound device and the networking device were working properly. Hence, the problem lies either with getting the drivers to start working again or with Windows. This is the first time this has happened to me in decades of using windows. The failure of the sound device and networking device occurred within one or two days of updating the latest Windows updates, March 12, 2009, on Microsoft's website. However, I can't be sure there is any connection.