Installing a New Device
Installing a new device requires both new hardware and new software. The steps you take depend on the device's Plug and Play status and whether Windows has an appropriate driver on hand.
Figure 8.1. When you install a Plug and Play device, Windows pops up messages in the notification area (system tray). You might see several such messages, ending with the one shown here. If you do, you're in luck; the new hardware is ready to use.

1. Run the device's setup program (if any).Many new devices come with a Setup CD or floppy that includes driver files. Run this program before you connect the device so that Windows can copy the drivers to your hard drive and have them handy for the next steps.2. Connect the device to your PC, as described in the preceding section.On the Windows desktop, one of the following three things will happen:A Found New Hardware pop-up message appears (Figure 8.1 ), meaning that Windows has installed the appropriate driver for your Plug and Play hardware. You're done.
Driver Information (.inf) Files
When Windows searches for a driver, it's actually looking for an information (.inf) file, which lists the driver files to use and registry entries to make. Windows veterans may recognize that .inf files and Windows 9x initialization (.ini) files are quite similar. But .inf settings are subtler than .ini settings. Never edit an .inf file to try to solve your driver problems.Hardware setup software can include an .inf file; a .sys file (the actual driver); and subordinate library (.dll), help (.hlp), Control Panel (.cpl), and web-page () files. Some device drivers are only .inf files. A monitor, for example, may be set up by a single .inf file listing the valid resolutions, refresh rates, and other display settings.The Found New Hardware Wizard appears (Figure 8.2 ), meaning that Windows detected the device but can't find an appropriate driver. Follow one of the "To install a device driver" procedures later in this section.
Figure 8.2. You'll see the Found New Hardware Wizard if your device isn't Plug and Playor if it is but Windows can't find an appropriate driver. This wizard helps you install the driver manually.

Tip

1. Insert the device's setup disk into a drive.2. On the Welcome page (refer to Figure 8.2), select the first option, Install the Software Automatically (Recommended); then click Next.The wizard searches the CD, floppy disk, and all removable drives.If the wizard finds one compatible driver, it installs the driver automatically. If it finds several compatible drivers, it lets you choose one from a list. If it can't find any compatible drivers, the wizard displays Figure 8.3 .
Figure 8.3. You have two choices here: Click Finish to give up the installation (at least for now), or click Back to enter the driver's specific location. Check Don't Prompt Me Again if you don't want to be nagged to install this particular piece of hardware each time you restart Windows.

To install a device driver downloaded from the internet:
1. On the Welcome page (refer to Figure 8.2), select the second option, Install from a List or Specific Location (Advanced); then click Next.2. On the Search page (Figure 8.4 ), select the first option, Search for the Best Driver in These Locations.
Figure 8.4. If you've downloaded a driver to a local or network drive, use this page to specify its location.

Tip

1. On the Welcome page (refer to Figure 8.2), select the second option, Install from a List or Specific Location (Advanced); then click Next.2. On the Search page (refer to Figure 8.4), select the second option, Don't Search, I Will Choose the Driver to Install; then click Next.3. On the Hardware Type page, select the type of hardware that you're installing (Figure 8.5 ); then click Next.
Figure 8.5. If you're installing drivers from a CD or floppy, it isn't important to pick the correct hardware type; the driver information (.inf) file will specify that.

Figure 8.6. Clicking an entry in the Manufacturer list makes the Model list display the drivers that XP has on tap for that manufacturer. If you don't see your model (or something compatible), click Have Disk to install a driver from a CD or floppy.

Tips

Figure 8.7. This warning appears if Windows thinks that you've chosen a driver that won't work with your new device. Click Yes if you're sure that you want to install the driver; click No otherwise.
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Figure 8.8. The most stable systems run only signed drivers; installing an unsigned driver is a gamble. If you see this message, check the device maker's web site for an updated driver. If you decide to click Continue Anyway, create a System Restore checkpoint first (see "Restoring Your System" in Chapter 19).


Figure 8.9. Ignore lets you install an unsigned driver without having to click through a warning message. Warn (the default) lets you install after you override the warning message. Block prohibits installation of any unsigned driver.

Figure 8.10. Windows displays several warnings when it blocks a driver, culminating with this one. You also may see an Incompatible Hardware or Software message box that provides details about the bad driver.
