Want to see something funny in Windows? Navigate to C:\Windows. Right-click on "twain.dll" or "twain_32.dll", then select "Open With..." ("Choose Default Program..." in Vista). Check "Select the program from a list", then select Notepad. Make sure "Always use the selected program to open this kind of file" is UNchecked. Click "OK". Then, go to Edit>Find... (or hit Ctrl+F) and type in "why".  Click "Find Next", and read the only result.

If you google around for the phrase, you might find out that it is usually part of a problem, and is found in a log file. However, in the two files I listed, it appears even with a fresh install of the OS, so finding it does NOT indicate a problem with your computer. Before you ask, yes, I actually found this file less than an hour after installing Vista on a brand new hard drive. No new programs were installed, no settings modified, nothing toyed with. It was simply a clean install of Vista.

Note that this works in XP and Vista. For any other Windows OS, your mileage may vary. I would assume that Windows 7 would also have this, and same for Windows 2000. And just in case you're wondering, if you have a Mac or a Linux box, you won't find this.