Manual uninstallation of a driver via the device manager can be useful if you are experiencing issues with it, for example audio, video or webcam devices which may stop working. These can be due to driver issues which may be installed incorrectly although WIndows reports the driver as installed.
First uninstall any application related to the program e.g. audio, video, webcam application. Press [Windows] and [e] and go to uninstall or change a program:
This will bring up a list of installed programs:
Double click the program related to the device to begin the uninstall. Repeat if there are multiple programs. Restart the computer if prompted.
Next open the Device Manger. Press the [Windows] and [Pause|Break] or [Windows] and [e] (to open computer) and then select properties.
On this screen next select Device manager.
Expand the device category you are interested in. In this example I will uninstall the webcam so I will look under Imaging Devices. Right click the device you want to uninstall, in this case the integrated webcam and select uninstall.
In Windows Vista/7 ensure that this box is checked and then press OK. In Windows 8 this box isn't here so just select OK.
You may be prompted to restart your computer however at this stage I would hold off the restart.
I recommend running CCleaner (both the cleaner and registry cleaner). For instruction see Using CCleaner and Defraggler.
Once you have used CCleaner's cleaner and registry cleaner restart the computer.
Upon reboot Windows should look for a generic driver for the device or won't find a driver.
You can now try reinstalling the driver for the device.