explorer.exe has generated errors

My os is windows2000. When clicking on the Windows Explorer button, or My Computer, Search, and Settings, the following error message appears “explorer.exe has generated errors and will be closed by Windows. You will need to restart the program. Anerror log is being created. I have previously downloaded service pack SR3. I tried repair from the windows 2000 installation cd to all no avail. I also deleted the last downloaded program before the error appeared. My current version of Norton AntiVirus detected no viruses. Is there something that can solve this problem without having to reinstall Windows2000 and having to re-install all the programs.
Thank you for your help,
Jerry Grubner