I had to replace my motherboard recently and then had to repair XP home.
Now it seems I no longer have SP2, can't get certain automatic updates, and
can't download SP2. I have in device manager:

Device;
Microsoft System Management Bios Driver
PNP Device ID;
Root\System\0002
Error Code;
39

Also when I close IE or Windows Explorer I get a box with a title bar;
Microsoft Visual C++ Runtime Library
Runtime Error!
Program C:\Iexplore.exe
This application has requested runtime to terminate it in an unusual way
Please contact the application's support team for more information.

Then I get a box following that which says;
The instruction at 0x00df296d referenced memory at 0x00d9f0d0. The memory
could not be read.
The f296d type of stuff changes a little each time, but it is substantially
the same for Windows Explorer and Internet Explorer. Thank goodness for
Firefox.