virtualbox.org

Hello. I`m using guest and host Win XP Pro SP3 . On guest system doesn`t work properly USB CDMA modem AnyData ADU-300. Its driver consists of two parts - modem itself driver and usb-to-serial controller driver. The problem is that when I plug modem (with blank usb filter) it works correctly with COM3. But if I plug another usb-device (e.g. flash-drive), modem stops response, but still remain plugged and identified by guest system, so I cannot connect to it.

In other hand, if I first plug flash-drive, and then modem, guest system installs its drivers again and modem becomes "visible" on COM5 or COM7 or COM9 depends on what usb-slot it plugged. But still doesn`t work.

Often it works once (!) and then freezes. So if I connect to Internet one time and the disconnect, I must unplug and then plug again modem. Its ridiculous.

Oh, one more thing. I found the way to get it work together - first plug the modem, connect to internet, then plug other usb devices. This system works fine until connect is alive

On host it works well.

Any thoughts? All will be helpful.

Unfortunately this is what I see on all USB devices when run in a guest (at least under Windows Host)
You can file a ticket with bugtracker (find one and add yourself to the ticket)
You will need to setup an account there as this account is different.
Link to bugtracker is below my post.

Any special reason that you need to use the modem in the guest? Usually its better to connect that on the host and then use it from the guest via bridged networking, or something.