1.
Operating System. Windows 98 Standard Edition or Second Edition?
2.
Safe Mode. Boot to Safe Mode. Does the problem occur while in Safe Mode? Tap either F5 or F8 function key once or twice per second while starting system to access safe mode.
3.
File Versions. Search system to see where these files live and how many copies you have? What are their version numbers?
3.
Memory Diagnostics. Test the system RAM for faulty memory.
MemTest86 provides "free" memory diagnostic downloads to make bootable diagnostic floppy or CD. It's the "Free Download" link left side of web page.
4.
System File Checker (sfc). Use the sfc utility to check for "
corrupt" system files. Don't correct any yet; just list the corrupt files found, if any. May be invoked via "Start" -> "Run" -> enter "sfc" in text box and hit Enter key.
5.
Incompatible DLLs. See the "possible solution" to the
DLL Problem subsection on that web page. It explains why this is sometimes an intermittent problem.