You may want to try System Restore to undo recent changes.
XP boots and comes up just fine. But, when I double-click a program icon like IE or Turbo Tax, nothing happens. After doing this, if I bring the mouse pointer down over the taskbar it turns into an hourglass, then back to a pointer if I move it up. My system just sits like that forever and never brings up the program.
Chowhound
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