After viewing several postings on this website to try to solve my appcompat.txt problem, I have learned how to delete it. However, even after a disk cleanup, defrag, and cold restart, the same error message pops up anytime I try to play any of my games. Most of my games are fairly new, examples include neverwinter nights, warcraft III, Spellforce, and Unreal Tournament 2004. All of these programs, after about a half hour to 45 minutes of play, will start looping the audio or visual screen currently active for about 30 seconds, and then the error report message pops up. When this occurs, appcompat.txt saves itself in a new folder under the path it specifies. I noticed this problem about 2 weeks ago. Some people attribute it to directX, others windows update, which I do use, and some attribute it to adware. I've run Norton Antivirus 2002 with full updates to that program, and every option says that the computer is totally clean. I know that there are many other people out there having this problem, and if anyone knows an exact solution, please reply to this post or email me. Note: Although this is categorized under windows 2000 or 4.0 or whatever, I'm running Windows XP home edition