A few people have reported problems with Office 2007 SP2 breaking things (such as the blue new message alert) after installation. Before uninstalling it or using system restore, try rebooting. Even if the installation forced a reboot, reboot Windows yourself. It often works wonders and if the problem still exists, uninstall or use system restore.
In my experience, especially when several updates are installed at the same time by Microsoft Update, uninstalling the update suspected of causing problems, rebooting then reinstalling it later works just fine.
Published April 30, 2009. Last updated on May 17, 2011.