Nokia lumia 900 is windows phone of nokia company. Drivers are in different types like pc drivers, Mobile drivers and many others. The drivers are used for different works. Similarly Nokia lumia 900 is best java phone you can use it different works like exchanging of files and can use internet with the help of this usb driver. This driver can support for detect your mobile in computer. If you haven't usb driver of your mobile in your pc you can't access these all things easily. So you i you haven't usb driver you will need to download latest usb driver first and just install it on your pc.
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