Installing a BB modem required me to load the drivers 1st and connect the USB line only when requested during the process.
Installing an external HD (in Win98SE)- the same, in fact the system only woke up to this one, when the USB plug was shoved in after all else was running.
This may have nothing to do with your problem, but it might be the best way to try.
Just to confuse. Long ago the SCSI scanner caused mayhem until I offered the Twain software AFTER the system was up and running.