System Restore in Windows 98 Before Windows Me

Before the automated System Restore utility debuted in Windows Millennium Edition (Me), Microsoft Windows 98 relied on a decentralized combination of automated registry backups, MS-DOS command-line tools, and system file verification utilities to recover from system crashes and configuration errors. Instead of creating comprehensive snapshots of the entire operating system, Windows 98 focused specifically on preserving core system configuration files—primarily the registry and legacy initialization files—which were the most common causes of boot failures.

The core mechanism for restoring stability in Windows 98 was the Windows Registry Checker tool, implemented through scanregw.exe in the graphical environment and scanreg.exe in real-mode MS-DOS. Every day during the first successful boot, Windows 98 automatically scanned the registry for corruption and created a compressed backup archive. These backups were stored in the hidden C:\WINDOWS\SYSBCKUP directory as Cabinet (.CAB) files named rb000.cab through rb005.cab, with the operating system retaining up to five backups by default.

Each backup archive contained the critical components required to initialize Windows:

  • SYSTEM.DAT (the machine-specific registry)
  • USER.DAT (user profiles and preferences)
  • SYSTEM.INI (hardware and legacy driver configuration)
  • WIN.INI (desktop environment and application initialization)

When software conflicts or registry corruption prevented Windows 98 from booting, users could not use a graphical rollback wizard. Instead, recovery required restarting the computer into MS-DOS mode, either by holding the Ctrl key during boot to access the Windows 98 Startup Menu or by booting from a floppy Emergency Startup Disk. Once at the command prompt, the user executed the command:

scanreg /restore

This command launched a text-mode interface displaying the available .cab archives alongside their creation dates and status (such as "Started" or "Not started"). Selecting a known working backup automatically extracted and replaced the damaged system and registry files, allowing the user to reboot into a previously functioning state.

For corrupted or missing dynamic link libraries (DLLs) and system drivers, Windows 98 provided the System File Checker (sfc.exe). Accessed from the System Information tool, it scanned critical operating system files against an internal database. If it detected unauthorized modifications or corrupted versions, it prompted the user to restore the original versions directly from the Windows 98 installation CD-ROM or stored .CAB installation files.

Unlike the subsequent System Restore feature in Windows Me and Windows XP, Windows 98 lacked an automated, continuous file system filter driver to track file modifications in real time. It could not automatically generate restore points prior to driver installations, nor could it roll back non-registry executable files automatically. Recovery in Windows 98 remained a manual, registry-centric process dependent on daily scheduled archives and real-mode DOS intervention.