win7 does not recognise usb dock replicator

[EvoT61]

Hey there, i have one of these everything works but not vga port. i have spare monitor at home and i want to plug in troug this usb port thing but i cant, nothing is happening. win7 says that cant recognise drivers, so i downloaded from lenovo web site and still ... nothing. usb and audio works ok. anyone had any problems with it ?