My External USB 4 port HUB is not detecting more than one device. What could b the reason ?

Is it bcoz its without adapter? do i need 2 try one with adapter? its working in other machines... By Himantry to get a driver for the ....
First, make sure the USB is active (turned on) in the BIOS. If it is, goto (Windows) control panel and disable the USB device. Next re-enable it. Sometimes this clears a conflict without having to change anything. If this does not work. Look for an IRQ conflict.