CHAPTER 16 INSTALLING DRIVERS

	Introduction :
	A driver is a program that controls the behavior of devices connected to a computer. It provides a connection between peripheral devices and the operating system. All devices such as monitors, modems and printers require drivers for their functioning. Drivers for certain devices such as the keyboard form a part of the operating system. Other devices like printers need to have their drivers installed separately.
16.1 Use of Drivers
	Every device has certain specialized commands that control it's functioning. Only the device driver has knowledge of these commands. The computer interacts with the different devices with the help of commands. The application programs and operating system of a computer send the commands to the devices. These commands are sent in a high-level programming language. A device can only function on the basis of its specialized commands. As a result, it cannot understand the commands sent by the computer. The device driver converts the commands from the computer to the specialized commands of the device. The function of a device driver is to act as a translation medium between the device and the operating system of the computer. For example, the driver for a laser printer will convert the data from the operating system to a series of laser signals. System Device Driver Device
	Working of a Driver
	The uses of a device driver are : _ Updates - Enables updates for a hardware device, independent of the operating system.We can thus add new functions to a hardware device, without making any changes to the operating system. _ Troubleshooting - Used in case of a problem with a hardware device. Replacement of the driver can be an effective solution. As a result, the device itself does not have to be replaced. _ Better Performance - Provides for better usage of the system. Usage of better device drivers greatly enhances the overall capabilities of the entire system. Thus, the entire system offers a better output, though the changes are only made in the device driver. This offers a great advantage in terms of cost.
16.2 Viewing Device Drivers
	Users can test the status of a device driver. This helps users to identify drivers that are not working properly. You can check whether the driver is working properly. You can also check whether a driver is installed for a particular hardware device.
	Hands on exercise
	To view existing drivers: 1. Select Start _ Settings _ Control Panel. The Control Panel window is displayed.
	Control Panel
	2. Double-click theSystem icon. The System Properties window is displayed.
	System Properties
	The General tab is displayed by default. This tab contains details of the computer. 3. Click the Hardware tab. The Hardware tab is displayed.
	Hardware Tab
	_ Hardware Wizard - Allows the user to install, configure, repair, and uninstall the hardware devices in the system. __ Device Manager -Provides a listing of all the hardware devices installed on a computer. This section contains the Driver Signingand Device Manager tabs. The Driver Signing tab enables users to set File signature verification settings. The Device Managertab allows users to change settings of any hardware device. 4. Click the Device Manager button. The Device Manager window is displayed.
	Device Manager
	This window lists the different hardware devices in the computer. Question marks to the left of the devices indicate that they are unknown devices. Unknown devices can be a result of faulty hardware, or because the device does not have a proper driver installed. 5. To view the working status of any device, double-click the particular device. 6. Suppose you want to check the working of the CD-ROM drive of your system, double-click
	DVD/CD-ROM drives.
	7. The CD-ROM drive or DVD drive installed in the system is displayed. Double-click the CD-ROM drive whose status you want to study. The CD-ROM Properties dialog box is displayed.
	CD-ROM Properties
	The Device statusgroup box shows the working status of the CD-ROM drive. The Troubleshooter button is used in case of any problem with the device. 8. Click the Properties tab if you want to change any settings in the CD-ROM drive. The Properties tab is displayed.
	Properties Tab
	The Propertiestab contains theCD Player Volume slide bar and theDigital CD playback option. 9. Click theDriver tab to view details of the device driver. The Drivertab is displayed.
	- Driver Tab
	TheDrivertab displays different properties of the driver, like the company that created the driver, the date of creation, the version number and the signing status of the driver. The different buttons in this tab are: _ Driver Details - View the details of the driver files. _ Uninstall -Uninstall the device driver. _ Update Driver _ Update the driver files of the driver. 10. ClickOK.
16.3 Driver Signing
	Device drivers communicate with the operating system and application programs in the computer. Hence, they can have access to certain protected parts of the system that are inaccessible to other programs. Device drivers that are of poor quality can cause serious damage to the computer. Devices work with drivers that are compatible with the operating system. You must only use reliable, high quality device drivers. The Microsoft Windows Hardware Quality Lab (WHQL) test program certifies device drivers that meet a certain standard. This test certifies drivers that are manufactured by Microsoft or independent developers. A digital signature is embedded in the device drivers that pass the WHQL test. It implies that the device driver has passed the Microsoft WHQL test. These drivers are called signed drivers. The digital signature applied by Microsoft uses cryptography to make the signature secure. The operating system will automatically recognize the digital signature embedded in the driver. If the driver is updated in future, the cryptographic signature will no longer be valid. Updated drivers have to go through the testing process again to get a new digital signature. The different hardware devices that can be certified for use with Windows 2000 include : _ Keyboard _ Monitor _ Modem _ Printer _ SCSI Adapter _ Smart Card Reader _ Multimedia Device _ Hard Disk Controller _ Mouse _ Network Adapter If the driver file of the new device is incompatible with the operating system or unauthorized or uncertified, then this can cause serious problems in the working of the system. Some devices like keyboards have their drivers installed automatically after the device has been installed. There are devices like printers that need their drivers to be installed manually. Automatic installation of a new unsigned device driver can lead to the following problems:
	_ Installation of inferior drivers -
	Takes place because the driver will be installed without any warning to the user. The user will not have any clue about the installation of a new device in the system. Poor quality device drivers can corrupt system memory. They can also cause errors in the functioning of the system.
	_ Overwriting of system files -
	Occurs when the new driver file has the same name as that of an existing system file or driver file. Overwriting of system files or driver files that are used by applications or devices will give rise to incompatibility problems. The devices that use these files will stop functioning. The working of the entire system will deteriorate.
	_ Viruses -
	Can result in introduction of viruses in the system. This will lead to numerous security risks. Viruses can lead to data corruption and system damage.
	_ Installation of incompatible drivers -
	- Installs drivers that are incompatible with the operating system. This happens because the operating system does not check for compatibility. The Windows 2000 operating system has a driver signing policy. Driver signing is the process of verifying whether a device driver is signed and has been tested for compatibility with Windows 2000. There are three modes for driver signing. The various modes enable different security settings regarding installation of unsigned drivers. If you have a branded Windows 2000 machine, the device drivers will be HCL-compliant. Also, drivers that are downloaded from Windows Update will be certified versions. Devices that have the logo Designed for Windowswill have digital signatures on them. Hands on exercise. To set the level for driver signing: 1. Open Device Manager.: 2. In Device Manager, click theDriver Signingtab. TheDriver SigningOptions window is displayed.
	Driver Signing Options
	The three options forFile signature verificationare: _ Ignore - Allows all drivers to be installed on the computer, irrespective of whether they are certified by Windows or not. _ Warn - Displays a warning message whenever an unsigned driver is about to be installed. _ Block - Prevents installation of unsigned device drivers in the computer. 3. ClickOKafter selecting the appropriate option forFile Signature Verification.
16.4 Complying with HCL
	Microsoft maintains a list of devices that have passed the compatibility test of Microsoft Windows and are of high quality. This list is known as Hardware Compatibility List (HCL). The Windows 2000 HCL contains a list of the devices that are compatible with the Windows 2000 operating system. You can comply with the HCL by ensuring that Microsoft has certified all the devices connected to your computer.
	16.4.1 Using the Driver Signing Options
	An effective way of complying with HCL is by using theDriver Signing Options.By setting the File Signature Verificationmode toWarn or Block,you can prevent the installation of uncertified or low quality drivers on your computer. Only a person with administrative rights can reduce the security level of the File SignatureVerification mode. If the mode is set to Block, only an administrator can change it toIgnore or Warn.A normal user can always increase the security level. If the mode is Warn, any user can set it to Block.
	16.4.2 File Signature Verification Tool
	You can check your computer for the presence of any unsigned system files or driver files. This is a good practice for keeping the system safe from uncertified driver files that can cause great damage. It is possible to recognize and deal with unsigned driver files and system files with the help of the File Signature Verification tool.
	Hands on exercise
	To detect unsigned drivers in a system: 1. Click theStartbutton _ Run. 2. TypeSigverif.exein the Rundialog box. TheFile Signature Verificationdialog box is displayed.
	File Signature Verification Dialog Box
	3. Click theAdvancedbutton.The Advanced File Signature Verification Settingsdialog box is displayed.
	- Advanced File Signature Verification Settings
	4. Select theLook for other files that are not digitally signedoption. Figure 16.12 shows the
	- Look for other files that are not digitally signed option
	5. Enter D:\Winnt\System32\drivers in theLook in this folder:text box. 6. Click theLoggingtab. TheLoggingtab is displayed.
	Logging Tab
	7. Ensure that theSave the file signature verification results to a log filecheck box is selected. 8. ClickOK.The File Signature Verificationdialog box is displayed. 9. Click theStartbutton. The File Signature Verificationprogress screen appears.
	- File Signature Verification Progress
	10. The Signature Verification Results dialog box is displayed.
	Signature Verification Results Dialog Box
	11. Click Close.
16.5 Installing Drivers using Add/Remove Hardware Wizard
	You can install device drivers for your system using the Add/Remove Hardware wizard. You must have administrative rights on a computer to use the Add/Remove Hardware wizard. You can also use this wizard to check the working status of a device and for troubleshooting. To use the Add/Remove Hardware Wizard: 1. SelectStart _ Settings _ Control Panel. The Control PanelWindow appears. 2. Double-click Add/Remove Hardware. The Add/Remove Hardware Wizard appears.
	- Add/Remove Hardware Wizard
	3. Click Next. The Choose a Hardware Taskscreen is displayed.
	Choose a Hardware Task
	4. Select the Add/Troubleshoot a device check box. Click Next.The New Hardware Detection screen is displayed.
	- New Hardware Detection
	Windows searches for new plug and play hardware to install. 5. After Windows searches for hardware, the Choose a Hardware Device screen is displayed.
	- Choose a Hardware Device
	6. Select Add a new device form the Deviceslist box. ClickNext. TheFind New Hardware screen is displayed.
	- Find New Hardware screen
	7. Select the No, I want to select the hardware from a list check box. The Hardware Type screen is displayed.
	- Hardware Type
	8. Select the type of hardware you want to install from the Hardware typeslist box. Click Next. 9. Select the manufacturer and the model of the device. Click theHave Diskbutton. 10. Insert the disk and follow the instructions in the wizard to install the device you want.
16.6 Viewing Hardware Devices in Windows 2000
	In Windows 2000, you can view all the hardware and software device drivers using the Computer Management Console. You can also use the Device Manager console to manage hardware device To use the Computer Management Console: 1. Right-click My Computer. 2. Select Manage.The Computer Management Console is displayed.
	- Computer Management Console
	3. Click Device Manager under System Toolsto troubleshoot or manage device drivers. 4. Double-click System Information.The different options underSystem Informationare displayed.
	- Options Under System Information
	5. Double-clickSoftware Environment. The different options underSoftware Environment are displayed.
	- Options Under Software Environment
	6. Double-click Drivers.All the driver details such as type, status, name, description, and state of each device driver is displayed.
16.7 Troubleshooting
	You must be very careful while handling device drivers. Any incorrect operation with respect to hardware drivers can cause great harm to the system.
	Best practices
	1. Read and understand the instructional manual or text file that is supplied with the driver. Incorrect installation or updating of drivers can corrupt the operating system. 2. Keep in touch with driver manufacturer for latest updates. Drivers usually get updated many times in a year. Search the manufacturer's web site for available updated versions of the driver. It is also useful to check for updated versions of drivers on sites such as www.driverzone.com and www.drivershq.com. 3. Be very cautious in following the instructions when you are uninstalling a driver. This may be required when you are updating your driver and the instructions require you to uninstall the previous version.
	16.7.1 Computer does not Work Properly after Installation of New Driver
	Your computer may start displaying blue screen errors or stop working properly after a new device driver has been installed. The computer may also restart randomly. This problem may be caused because of the newly installed driver, if it is an inferior quality driver. It can also be a result of incompatibility between the driver and the operating system. To solve this problem, remove or uninstall the device driver. After uninstalling the device driver, restart the computer. If the device driver is the cause, the computer must behave properly. In such a case, report the problem to the driver manufacturer. You can also try to obtain an updated version of the driver from the Microsoft Windows Update website.
	16.7.2 Computer does not Update a Driver in Memory
	If you update a device driver, the driver file must be updated in the computer memory. This does not happen in some cases. The driver file is updated in the computer memory only after you restart the computer. Additionally, the computer does not prompt you to restart after the installation process is complete. This problem can occur in case both the following statements are true: 1. You have used theUpdate Device DriverWizard in Device Manager to update the driver. 2. You are updating a driver that is being used by more than one device. To overcome this problem, manually restart the computer after you complete the installation of the updated driver.
	16.7.3 Cannot Download Driver Updates from the Windows Update Site
	You can download updates for your device drivers from the Windows Update site. In some cases, the installation does not succeed. This problem generally occurs if there are a lot of Inf files in the Windows directory folder %windir%\Inf. In this case, the entire Inf folder is searched for updateable driver files. It is only necessary to check the installed driver files. This causes the above problem. You can solve this problem by getting the latest Windows 2000 service pack. A service pack is an update of software that contains additional features and solutions to bugs in the earlier versions of that software. The Windows 2000 service packs help to keep the product up to date. It contains updates, administrative tools, and drivers. You can download the Windows 2000 service pack from the Microsoft site.
	16.7.4 Device Driver Error Message is Displayed
	When you try to take your Windows 2000 computer to Hibernate mode or Standby mode, you may receive an error message that states, the device driver for the 'PC/AT Enhanced PS/2 Keyboard (101/102-Key)' device is preventing the machine from entering hibernation. Please close all applications and try again. If the problem persists, you may need to update this driver. The above error occurs when a program installs a kernel-mode driver. The kernel-mode driver then attaches itself to the keyboard driver. Adobe Type Manager 4.0 is a program that can cause this problem by installing the kernel-mode driver. To resolve this problem, uninstall the program that is installing the kernel-mode driver. Then restart the computer. Contact the manufacturer of the product for an updated version of the product that is compatible with Windows 2000.
	16.7.5 Network Adapter does not Work
	After you have installed Windows 2000 or upgraded to it, you may experience problems with the network adapter. This can lead to loss of network connectivity. The computer may show that the network adapter does not have a driver installed. The network adapter may have worked fine before the upgrade. The main cause of this problem is that the network adapter is not compliant with Windows 2000. If you have installed a network adapter that is compliant to Windows 95, Windows 98 or Windows NT, it need not work with Windows 2000. To solve this problem, uninstall the network adapter and replace it with an adapter that is Windows 2000 HCL-compliant. You can also contact the manufacturer of the network adapter about the availability of an updated device driver that is Windows 2000 compliant.
	16.7.6 Registry Entry of One of Two devices is not Updated
	Some computers have two or more identical devices like a SCSI adapter and a network adapter installed. If you update the device driver for one of these devices, all the identical devices will use the updated driver. The driver information like the date and version number must be updated for all the identical devices. In some cases, only the device for which the driver is updated shows the updated driver information. This problem is caused because the registry entry is not updated for all the devices. To solve this problem: 1. Open Device Manager. 2. Double-click the identical device for which driver information is to be updated. 3. Click theDrivertab. 4. Click theUpdate Driverbutton. This starts the Update Device Driver wizard. 5. Follow the steps in the wizard to update the device driver.