Windows Vista: The Complete Reference (Complete Reference Series)

Windows stores its configuration information in a variety of files of different formats, including files for configuring Windows itself and files for running Windows and DOS programs. Windows comes with the System Configuration tool (or Msconfig, for short) to help make controlled changes to some of its configuration files. This chapter explains the configuration files used by Windows Vista, as well as how to run the System Configuration program.

What Kinds of Configuration Files Does Windows Vista Use?

Other than the Registry (described in Chapter 40), most of Windows' control information is stored in text files that you can open with Notepad or any other text editor. Although changing these files is usually a bad idea unless you're quite sure you know what you're doing, looking at their contents is entirely safe-and provides fascinating glimpses into how Windows works.

Making Configuration Files Visible

Most of the control information is stored in hidden, system, and read-only files (see "What Are Attributes?" in Chapter 9). Hidden and system files are like any other files, except that they don't normally appear in file listings when you use Windows Explorer to display a folder that contains them. (Any file can be hidden, but only a couple of required files in the root folder of the boot drive are system files.) Read-only files can't be changed or deleted.

You can tell Windows to show you all the hidden files on your computer. In an Explorer window, select Tools Folder Options and click the View tab. The list of Advanced Settings includes a Hidden Files And Folders category. Click the Show Hidden Files And Folders check box so that a check appears. This setting reveals hidden files in all folders, not just the current folder. Hidden files appear listed with regular files, but their icons are paler than those of regular files. To reveal the hidden files that Windows considers "special," uncheck the Hide Protected Operating System Files (Recommended) check box. Click Yes in the warning dialog box. Click OK when you have finished making changes in the Folder Options dialog box to make the changes active.

You can change a file's hidden or system status by right-clicking the file and selecting Properties. Click the Hidden and Read-only check boxes at the bottom of the Properties dialog box to select or deselect these attributes.

Windows Initialization Files

Since Windows 95, Microsoft has moved most Windows initialization information into the Registry, but Windows still uses two initialization files for 16-bit support: Win.ini and System.ini. Some Windows 3.1 applications stored their setup information in individual INI files (initialization files), such as Progman.ini for the Windows 3.1 Program Manager. Other Windows 3.1 programs used sections in the general-purpose Win.ini file.

All INI files have the file extension .ini, and nearly all reside in the folder in which Windows is installed (usually C:\Windows). All INI files have a common format, of which the following is a typical example (it contains configuration information for the WS_FTP file transfer program):

[WS_FTP] DIR=F:\Program Files\WS_FTP DEFDIR=F:\Program Files\WS_FTP GROUP=WS_FTP Pro INSTOPTS=4 [Mail] MAPI=1

You may see pathnames that include %SystemRoot% in a setting in a dialog box setting or in a configuration file. SystemRoot is a global system variable that tells Windows where the Windows program is stored. Windows replaces %SystemRoot% with the current location of Windows (usually C:\Windows).

Why is this useful? Because if you create a configuration file for your computer and then give it to a friend, your friend's Windows system may be installed somewhere else (for example, F:\Windows on a dual-boot system in which the C: partition is used by a previous version of Windows). Your Windows system could be installed on C: but theirs could be on F: or L: or Z:. Using %SystemRoot% in a configuration file's pathname allows it to work on any system, regardless of circumstance.

An INI file is divided into sections, with each section starting with a section name in square brackets. Within a section, each line is of the form parameter=value , where the value may be a filename, number, or other string. Blank lines and lines that start with a semicolon are ignored.

In general, editing the Win.ini or System.ini file is a bad idea, but if you need to do so, use the System Configuration tool (see "Configuring Windows with System Configuration" later in the chapter). You can take a look at the contents of the files using this program, too.

The Win.ini File

In Windows 3.1, nearly every scrap of setup information in the entire system ended up in the Win.ini file in C:\Windows, meaning that if any program messed up Win.ini, the system could be nearly unusable. More recent versions of Windows alleviate this situation by moving most configuration information into the Registry, but Win.ini is retained to offer support for 16-bit applications. You'll typically find sections for a few of your application programs in Win.ini, plus a little setup information for Windows itself.

You can use Notepad to edit Win.ini, but it can be dangerous. Be sure to make a backup of the file first.

The System.ini File

In Windows 3.1, the System.ini file in C:\Windows listed all the Windows device and subsystem drivers to be loaded at startup. In Windows Vista the vast majority of the driver information is in the Registry, but System.ini still contains driver configuration information for 16-bit applications. You can edit the System.ini file in Notepad or similar ASCII text editor.

The Registry

The Windows Registry contains all of the configuration information that is not in an INI file, including the vast majority of the actual information used to control Windows and its applications. Use the Registry Editor to examine and manage the Registry (see "Editing the Registry" in Chapter 40).