System File Checker checks for damaged or replaced system files, and then prompts you to replace any files that do not match the original Windows 98 files. (Uses your 98 CD)
To start System File Checker, follow these steps:
Click Start, point to Programs, point to Accessories, point to System Tools, click System Information, and then click System File Checker on the Tools menu.
Click on:
Scan For Altered Files
Any files SFC finds corrupted or missing will be copied over from the win98 CD.