virtualbox.org

I run PCLinuxOS 2009 and Win XP guests on both PCLinuxOS 2009 and Win XP
hosts. I use the same .vdi files for each host, ie. pclos.vdi and winxp.vdi.
When I first created these guests I installed my USB all-in-one printer (Epson RX620)
into both guests and could use it from both, together with my usb external hdd.
Now, however, I can access them from none of the combinations.
When I open VBox in Win XP host I get the following :
Failed to access the USB subsystem.
Could not load the Host USB Proxy Service
(VERR_FILE_NOT_FOUND). The service might not be
installed on the host computer.

Details
Result Code: E_FAIL (0x00004005)
Component: Host
Interface: IHost
{926469ca-9091-42ef-928e-582d78b66c70}
Callee: IMachine
{13420cbb-175a-4456-85d0-301126dfdec7}

USB is installed on the hosts and I have no problem with my usb printer or external hdd.
If I open vbox in PCLos I dont get this message but have no usb
Basically I have no usb on any combination of host and guest.
In both cases the version of vbox has usb support, ie. PUEL.
I have the same problems on a friends pc with a Vista host and XP Pro guest. Her usb printer,
Lexmark X5495 worked perfectly on installation but after restarting vbox the pinter was again
not accessible.
Can anyone help ?

Following this problem, I have uninstalled and reinstalled VBox 2.2.4 with no
difference.
In all cases, Settings - USB contains the filter for Epson RX620. The printer is 'seen'
from within the guests, but the guest does not seem to be able to talk to the printer.
After trying, my PCLinuxOS desktop contains 2 icons labelled
XSane /proc/bus/usb/001/003 and
XSane /proc/bus/usb/001/004
Hovering the mouse over them shows
dynamic_proc_bus_usb_001_003_dynamic.desktop and
dynamic_proc_bus_usb_001_004_dynamic.desktop.

Following a suggestion on http://www.virtualbox.org/ticket/4207, I switched on MSI logging when I reinstalled
onto Win XP, and the files are attached.
I dont get the error message from XP now, but the guest still cannot talk to the printer

How is the printer port configured? for example the bi-directional option often causes problems if two way communication doesn't work. If it doesn't work at all consider lpr/ldp printing by a Host share over tcpip. Also check port 9100 on the Host to be open for use by the Guest.