Setup and Startup

A cabinet (.cab) file is a compressed file that contains other distribution files, such as drivers and system files. Drivers are placed in a single .cab file on the Windows 2000 operating system CD. This driver .cab is used by both Setup and other system components that need to install drivers. The .cab file contains approximately 3000 files and is installed at:

%windir%\Driver Cache\<platform>\

The list of files is in Drvindex.inf. To view the .cab file, use Windows Explorer.

The benefits of using a .cab file include the following:

  • Does not require administrators to use a Setup CD to install new devices on the computer.

  • Does not require you to log on with local admin rights to install new hardware as long as the device is present in the .cab file and digitally signed. You can override this by deleting the .cab file from the drive.

  • Reduces the amount of bandwidth and installation time that is required for network installations. (Winnt32.exe and Winnt.exe copy a single file instead of many smaller files.)

  • Provides a simple way to install printer drivers. Administrators do not need to have the Windows 2000 CD to install printer drivers because most printer manufactures use Microsoft core printer drivers. For mobile users, the printer drivers are always available for quick printing.

  • Enables remote install services clients to install drivers for new devices locally. It also allows the Remote Installation feature to support different hardware between the source computer used to create the image and the destination computer installing that image. For more information about Remote Installation Services, see Customizing and Automating Installations in this book.

When a driver file is needed, Setup checks the Drvindex.inf file to see if the file is listed. If the file is listed and the .cab file is on your computer, Setup tries to copy the file from the .cab file. If a signed driver file is found in the driver cache directory and has the same name as the needed file, Setup uses this file instead of the one contained in the .cab file. If the required file does not exist in the directory of the .cab, the installation path is searched. If that fails, Setup prompts you to supply the required file.