dacs.doc electric

THE HKEY is Microsoft’s language for a program handle to a key that contains configuration information. A “key” looks identical to a folder or subdirectory, except that the name applies to levels and sublevels within the Registry. Looking at the various HKeys in REGEDIT is the same as looking at a drive in Windows Explorer. Each key is represented by a folder icon that can be expanded or collapsed just like folders and subfolders.

The Windows 95/98 Registry contains six primary HKeys. Each HKey is like a primary folder located in the root directory of a drive and has many levels of subkeys that descend like a directory tree. The root directory is called HKEY_CLASSES_ROOT. The six primary HKeys are:

1. HKEY_CLASSES_ROOT File extensions and applications used for OLE (Object Linking and Embedding)

2. HKEY_USERS Data stored in USER.DAT that keeps network information and user configuration options

3. HKEY_CURRENT_USER User information specific to the Windows 95/98 user at the moment (if networking is disabled, this is a duplicate of HKEY_USERS)

4. HKEY_LOCAL_MACHINE The hardware and software configurations for a computer (multiple configurations can be stored for the same computer)

5. HKEY_CURRENT_CONFIG Printers and display settings

6. HKEY_DYN_DATA Dynamic data in RAM having to do with how Windows 95/98 is running (shown by the System Monitor applet)

Remember. The Windows 95 Registry is a set of two files. SYSTEM.DAT is the main file and can become very large. USER.DAT is the second file, containing mostly configuration inforation. The Windows 95 Registry is built around six master sections (Hives) called HKey_[SectionName] where [SectionName] is the name of each specific section. At the top of the Registry tree is HKey_Classes_Root.

The section used for hardware is HKey_Local_Machine.
Information about hardware and software is stored in many places within the Registry, and uninstaller programs have varying degrees of success in finding all occurrences and references to their own programs. This substantiates the belief that a PC should be “trashed” and rebuilt (i.e. FDISK and format the drives) to truly eliminate problems.

When Windows 95/98 is set up for the first time, a SYSTEM.NEW file is created as the first Registry. This file contains the hardware and software configuration information made during the detection phase of Setup. If everything works well and Windows 95/98 starts successfully without crashing, SYSTEM.NEW is renamed SYSTEM.DAT.

Once Windows 95/98 is installed and working, the first successful
Registry (SYSTEM.DAT) is renamed SYSTEM.DAØ and held as a backup of the original Registry. The very first SYSTEM.DAT used when Windows 95/98 starts from the hard drive is also copied to SYSTEM.1ST in the root directory as another backup of the clean, first installation.

SYSTEM.1ST includes everything up to the first reboot of the system. If you replace SYSTEM.DAT with SYSTEM.1ST at any time and reboot the computer, you’ll get the “Starting Windows 95/98 For The First Time” screen and Windows 95/98 will go through the configuring hardware process, initializing the Control Panel, Start Menu, and all the other aspects of a first-time start. Windows 95/98 will then reboot and start up normally.

Every time Windows 95/98 starts successfully, it backs up STYSTEM.DAT to SYSTEM.DAØ and USER.DAT to USER.DAØ (overwriting any existing DAØ files). If something goes wrong, the DAØ files are used automatically on restart to return the computer to the successful previous startup.

Here is a summary table showing the names of the Windows 95/98 or Windows 3.x Registry files, where they are stored, what the backup files are called, and how they are edited.