Windows registry

In computing, the Windows registry is a database which stores settings and options for the operating system for Microsoft Windows 32-bit versions. It contains information and settings for all the hardware, software, users, and preferences of the PC. Whenever a user makes changes to "Control Panel" settings, or file associations, system policies, or installed software, the changes are reflected and stored in the registry.

On Windows 9x computers, an older installation can have a very large registry that slows down the computer's startup and can make the computer unstable. This has led to frequent criticisms that the registry leads to instability. However, these problems do not usually occur on the Windows NT family of systems, including Windows XP.

Editing the registry

A 'tuned-up' registry will mean a faster and more reliable system, and there are many options available for editing your registry. However, most can lead to critical errors or system failures without an advanced, expert knowledge of what you're trying to accomplish and how.

Don't fear though, there are safer and easier options available to the average user that will walk you through eliminating errors or clutter in your registry.

The Registry Toolkit is a good example of this and offers a free scan of your system for errors and clutter that may be causing your system to run slow or crash often.

Useful Registry keys

The following registry keys may be of interest to users attempting to customize their Windows systems.

• HKLM\System\CurrentControlSet\Control\FileSystem\NtfsDisableLastAccessUpdate Creating this (as a DWORD) and setting it to 1 will prevent Windows (NT, 2000 or XP) from tracking the last access time of files, which speeds up a lot of operations (especially opening folders of items with previews).
• HKLM\System\CurrentControlSet\Services\LanmanServer\Parameters\SizReqBuf Specifies the size of buffers used for storing requests to the file/print server. Increasing this from the default of 4356 bytes can improve network performance: a figure of 14596 is frequently recommended.
• HKLM\Software\Microsoft\Windows\CurrentVersion\Run (and the HKCU equivalent) specifies applications to run whenever a user logs in. A lot of malware uses this registry key to ensure it is automatically run, so it is a good place to start looking if you think you have an infection.