I have a weird problem on my Dell laptop with Windows XP SP2 system: my Alt key gets sometime "sticky". Say, when I press Alt-F4, my Alt key remains "pressed" and activates close confirmation (if any) box' system menu, or if I use Alt-Tab, then I end up with activated window's menu.
1) It's not a hardware problem: it replicates with laptop's own keyboard and external one.
2) "Sticky keys" are turned off.
3) As I'm heavy keyboard user, this drives me crazy.
Any ideas appreciated.