Click start control panel administration tools computer management device manager scroll through all of your devices or for Windows 7 click start right click on computer select properties in the left pane device manager scroll through all of your devices. If you see a yellow question / exclamation mark ? ! or a Red X you will need to update the drivers for this device right click select update driver/reinstall driver software. If you can see your usb device but its not working scroll to Ports(Com&Ltd) right click to update driver If you computer came with a motherboard disk the drivers could be on it. or you might have to download them Rather doing a driver hunt which can take hours. http://download.cnet.com/slimdrivers-free/3000-18513_4-75279940.html
Windows XP/Vista/7/8 This might take some time being a freeware driver solution Note: The Driver program will find all of your outdated drivers This will automatically search for and find the correct driver you will have to update every driver individually once you update you might be asked whether you want to restart or make a system restore point. Click no to both of these then continue updating each driver free then restart once all of the drivers have been updated. also at cnet http://download.cnet.com/2000-20_4.html
on the home page you should see a search tab just type in what you are looking for IE: Motherboard name sound drivers. Place a tick in either windows software or all software box. You might have to try a few times to get it right. http://download.cnet.com/drivermax/3000-18513_4-10572602.html
Windows 2000/XP/Vista/7/8 free driver program http://download.cnet.com/drivers-for-free/3000-18512_4-75548155.html
Windows XP/2003/Vista/Server 2008/7/8 free drivers http://www.downloadcollection.com/device_doctor.htm
Device Doctor is a freeware Windows application that scans your computer hardware and checks to see if there are new driver updates available for your devices. It also locates drivers for Unidentified Devices in the Windows Device Manager. This tool was designed to be very simple and easy to use http://www.innovative-sol.com/drivermax/
free program, paid update available Hope this helps.