VB sees card reader but Explorer in Win 7 cannot

[Walrus]

Been using Windows 7 in Bootcamp without a problem. Trying out VB. VB sees it (listed in USB Devices menu). But when I insert card into reader, I don't see it in Explorer. Windows 7 is up to date.

If I tick off the menu item, I get error:

Failed to attach the USB device SanDisk ImageMate CF Reader/Writer [9321] to the virtual machine Windows.

USB device 'SanDisk ImageMate CF Reader/Writer' with UUID {e6fd0563-db72-410a-a182-7cec9e07c940} is busy with a previous request. Please try again later.

Result Code: NS_ERROR_INVALID_ARG (0x80070057)
Component: HostUSBDevice
Interface: IHostUSBDevice {173b4b44-d268-4334-a00d-b6521c9a740a}
Callee: IConsole {1968b7d3-e3bf-4ceb-99e0-cb7c913317bb}

This all worked flawlessly in Bootcamp. I could insert card when booted into Windows or once Windows was running.

Any ideas how to fix problem? I don't want to use Shared Folders if I can help it.

Thanks.

[mpack]

I suggest you use Google to search this site for " "busy with a previous request" site:forums.virtualbox.org", as the USB question has been asked and answered many times already.

Why don't you want to use shared folders? They would be far simpler and more reliable - and just as safe - as what you are trying to do.

[mpack]

And would you clarify: you mention bootcamp, a feature of Mac hosts - but you posted in "Windows Hosts". What actually is your host OS?

[Walrus]

Sorry about posting in the wrong forum...The use of "host" is very confusing. Windows is being hosted on my Mac, so I assumed Windows Hosts to be the right forum. Anyway, that apart, the problem was solved by installing VirtualBox Extension Pack. I think VM could make it clearer somehow that's what's needed to have access to even basic USB devices, such as card readers and hard disk drives, which also wasn't mounted in Explorer, BTW. If it's unsafe to do so, then make is safer somehow.

On the subject of safety, I thought it would be safer to use an attached USB device to move files between Windows and Mac OS. I could be wrong.

Using a USB is device isn't straight forward. I have to shut down Windows before I can mount the device back in Mac OS and, I think, a device mounted in Mac OS isn't seen in Windows (need to test it as I only installed extension pack last night). I have filed a feature request for it to be released when focus is on Mac OS (I can see some problems if you go back and forth but maybe they can be overcome).

[mpack]

Moving to "Mac hosts".

It really isn't all that confusing: a host caters for guests. The Mac is your host, Windows is the guest.

On the subject of safety, I thought it would be safer to use an attached USB device to move files between Windows and Mac OS.

Shared folders theoretically introduce two kinds of danger: one is that the folder provides a medium through which malware might be transmitted between host and guest. A USB drive presents exactly the same danger hence is no safer. The other danger of shared folders is that the contents are visible to other PCs on the same network, hence potentially to a hacker as well. That is true for normal network shares, but is not true for VirtualBox GA shared folders, which are not really shared folders - they just seem that way to the guest OS. In any case, even with true network shared folders the solution is easy: don't keep stuff in the folder that you wouldn't want to share with the general public.

[Walrus]

So, seeing as I have to move content to card reader, I may as well create a special folder and dump it in there and then share it? If hacker can get to all content via a USB, there's no advantage in using it as far as I can see.