Mystery Dialog Box ?

Howdy all -
When I boot up my computer (XP Pro), a small dialog box pops up in the middle of the screen. It is entirely blank, except for an 'OK' button at the bottom. I have removed all programs from my computer except for the ones that I have been using for months with no problems. I run Ad-aware and Spybot:SAD religiously, at least twice a week, and I always update before I run them. I have defragged, I have peeked through the registry and my hard drive to look for the culprit, but I just cannot seem to get rid of it.
I have taken a screenshot of it so you can know exactly what I'm talkin' bout Willis, but since we can't attach files in these boards, if you need to see it to diagnose it, send me your e-mail address, and I can e-mail it back to youz. I have not made any hardware modifications in more than 6 months.
Thanks for your help!
patchworkblue@hotmail.com

AMD Athlon 2500+ Barton
DFI Lanparty NFII Ultra, Revision B
Geil 512MB PC3200 DDR
geForce 3 64MB (don't laugh, i'm poor)
onboard sound, network
WD 120GB 7200RPM HDD, EIDE, 8MB cache



Women--can't live with them, can't have heterosexual same-species intercourse without them.

Windows XP NEED to be "fixed" (refreshshshedly reinstalleded) every once in a while, the guess is that yozz time is up.

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