Issue: USB External HDD no longer accessible from inside my Win XP Pro VM. In the past I was able to select the external drive from the USB devices menu located on the bottom right of the VM window and Windows XP would detect the drive and give me access. Now when assigning the USB drive to the VM nothing happens. Windows does not detect any USB device; I've monitored Device Manager and nothing new is detected. I've also tried multiple external HDD's. It seems to be an issue with the Win XP OS, as I've tested it inside a Vista VM and the feature works fine. No changes to the OS have been made since this feature was working. When connecting the disk to the VM, there's a brief moment when the icons across the bottom of the VM window (Keyboard, Disc, HDD, Network, USB, Share) seem to double up/expand but it's too quick to define what it is.
Could you please go to the virtual machine(XP) configuration, click USB controller item there and make sure it is 'Enabled'. If so and the USB is not recognised, please remove the USB Controller with the '-' button and add it again with the '+' button.
The USB controller is currently enabled, but the option to remove either the controller itself or disable and re-enable is greyed out when the VM is running. The current workaround I have for this is to restart the guest OS, but this does not really suit me at all; having to restart the VM every time I connect a disk is not really a viable solution. In terms of the problem itself, it occurs when the VM is left in a suspended state, and then resumed. If it is shutdown then the issue is non existant.
After you have connected the USB storage device please check if it is present and checked in the Devices => USB menu in the Parallels Desktop toolbar. To make it connect to your VM please go to Parallels Desktop => Preferences, open the USB tab and select either 'connect to guest' or 'ask me what to do' options. In the former case all USB devices will automatically connect to the guest, in the latter every time you connect a USB device you will be asked where you wish to connect it to.
I have tried modifying the settings to be both 'Ask me what to do' and having the disk connecting automatically to both the VM and the host OS. In the case of the latter; after ejecting the disk from the host OS, I have then connected it via he USB menu of the VM. It always shows as available and the 'tick' next to the device is present after selecting it, but the guest OS does not detect anything until it is rebooted.
Doing that is fine. Until it doesn't work again. The same end result as restarting the OS. The disk is detected the first few times it is connected but then after a while it stops working.
Instead of shutting down & restarting your guest OS, you might want to try Control Panel => Add Hardware and scan for new plug & play devices. I have the same issue of having my USB HD not automatically recognized after resuming VM from suspension (with Windows Server 2003). The issue is resolved after scanning for new plug & play hardware.
Will try when I get home. Not really a resolution though, more a workaround. It shouldn't be necessary to do that to attach a USB device...