I am using an USB headset "Sennheiser PC35", it installs automatically on Windows XP, and the "Drivers" area on manufacturer site also says that it should install automaticaly so no driver is required.
However... on Windows 7 Pro (64bit I think) it says that the USB device failed to install correctly when I plug the USB cable, in device manager I see it as "USB Composite device" with an exclamation mark and details are "This device cannot start. (Code 10)", trying to update driver automatically or from online says it is already latest driver.
I tried all USB slots. Some users suggested I leave computer turned off and power unplugged for a while, I tried that too and I turned it on without any other usb plugged in. No effect.
Edit: I also tried the Vista 32 bit firmware update many articles refer to, but that one doesn't work for me on Win 7 pro 64bit.