U3 announced a bug prevents some applications from running on Vista. The problem occurs when your Vista computer has one or more non-U3 mass storage devices attached. A good example would be your PC having a card reader connected while trying to launch a U3 drive. Not all hope is lost as the error [message: #0x80040210 (DAPI_E_COMM_FAIL)] only occurs when that non-U3 device is connected with a drive letter assigned yet no media in the device.
U3 engineers are working on it. Check U3 support for updates.
