Windows XP Help Center (helpctr.exe)

"Help has stopped working.
The Help And Support Center uses two related modules: the Microsoft Help Center Service (Helpsvc.exe) and the Help And Support Center executable (Helpctr.exe). Under some circumstances, clicking the Help And Support Center icon might not produce a result. If you look in the Windows Task Manager, you'll see that both modules are running; you might also see multiple instances of Helpctr.exe, which could be causing your Help problems. To solve this problem, follow these steps:

1.. Press Ctrl+Shift+Esc to open Windows Task Manager.
2.. Click the Processes tab and then click the Image Name heading to sort the list in alphabetical order.
3.. Highlight each instance of Helpctr.exe in the list and click the End Process button. Repeat until all instances are gone from the list and then close Task Manager.
4.. Open Control Panel�s Services option (in the Administrative Tools group, under Performance And Maintenance Options).
5.. Select Help And Support from the list of services, right-click, and then choose Restart.
After completing this procedure, you should be able to restart the Help And Support Center."

This is from Windows XP Inside Out by Ed Bott.