Keyboard (?) input problem

Sorry for the vague title, but I’m not sure of the problem so I’m not sure of the title. Every once in a while, my computer seems to think I’m holding down the left arrow key. I can bring up any menu, but the computer still acts as if I’m holding down the arrow key (that is, the menus appear but cycle through).

Once it starts happening it affects all programs, all the way to the start>shutdown dialogue. I’m not sure when the problem arose, but it has lasted through two keyboards – the fist plugged into the PS/2 port and the current keyboard is USB. It may have begun after installing a Logitech cordless mouse (unrelated troubles there), but I unfortunately can’t say for sure. Besides, the computer acts as if the arrow key is pressed, while the mouse cursor stays in control. In any event, I’ve tried replacing the mouse batteries during a cursor attack, but to no avail.

Here’s the odd thing. At first the only way to get rid of it was to restart (you can imagine the problems trying to save a document when the arrow is stuck). Then after a bit of trial and error, I found that I can get my machine back to normal simply by going to Start>Log Off User>Switch User, and selecting myself again – poof, no stuck arrow!

But that’s a PITA, and I’d really like to know what’s going on and actually solve the problem, not the symptom. Other than changing the keyboard and port, (which was done), I have no idea how to diagnose this. Oh yeah, Spybot, Adaware, and AVG come up clean.

If it makes a difference, I’m on a home-built:
XP Pro SP2 and all patches
Asus NForce4 M2N4 SLI
Athlon 64X2 4800+
2 GB Kingston RAM
Microsoft USB Natural Keyboard 4000
Logitech MX610 mouse

Oh, and bonus points if you can help get “Me and My Arrow” out of my head



I have had similar problems (keys that don’t work at all). Rebooting would solve it temporarily (I didn’t think of trying to switch user), but I finally gave up and reinstalled the OS. I think that has cured the problem. It is a computer that I have reinstalled the OS on a number of times, so I think there is a defective spot on the disk.