My problem started two days ago with some general slowdown and unreliable behavior from my Windows 7 Vaio laptop, as well as the unwanted appearance of Babylon search as the default for all my browsers. (Not sure what caused the infection, but I was recently away for a long business trip and my kids have had more unsupervised computer time than usual.) I removed Babylon from my computer, but when I went to update my Trend Micro antivirus program, it was disabled and could not update. I couldn't get any other antivirus to work. I ran across a related thread on these forums and tried Combofix, which ran successfully and created a log. Then I saw that I should have started with the guide, and I proceeded to work my way through those steps. Afterward, having not yet found an obvious problem, I also ran Bazooka. I've clearly made some progress, because at one point I couldn't update or run MalwareBytes and now I can, but it did not find any problems ...in spite of the fact that I still can't install an antivirus program like Avast or Antivir. Hoping the community here can help me find the insidious cause of my problems. Here are my logs, and thanks so much.