Question concerning windows live onecare. Getting an error WDDM service not running. What is this error?
This isn't at all regarding OneCare. WDDM is the Windows Display Driver Model in Windows Vista, which differs from the way the display is handled in XP. It isn't a service.
It may refer to your Western Digital External Drive. If you have a Western Digital My Book and have installed the supplied software, uninstall it and, if you use the WD software, reinstall it.
If OneCare is in green status and running, you question might better be posted to the Vista forums here: