I too am having the USB2 external hard drive issue in a Win XP Pro VM under Parallels Build 3120. Connection is detected, and shows up under USB mass storage devices in system/devices. Does not mount under My Computer.
The drive is a FAT32 formatted 300GB SATA hard drive with two partitions and mounts fine under OS X and native Win XP Pro.
MacBookPro 2.16 Core2 Duo/120GB/2GB, OS X 10.4.8
Last edited: Jan 24, 2007