I would be curious to know if the SanTuo.txt file re-appears if you disconnect the computer totally from the web. I know that some people have suggested an external influence may be creating this file, and this test may prove or disprove that theory. Also, and this is going to sound insane, but try temporarily write protecing the area where the file gets written to. There is an outside chance that Windows will return an error, and you can see what process is causing the write (hey, I said it was a stretch!)