My experience with SpybotSD 2 was not a good one. Acer Laptop computer came with McAfee Security Suite as a 3 month trial version which I removed. I installed Spybot - Search & Destroy 2 and then noticed an Action Center message stating that Windows Defender (the default Virus Checker replacing MS Security Essentials in Windows 8) was turned off. I tried using the Services under Administrative Tools to turn it on, but it would NOT stay turned on. I had to uninstall Spybot - Search & Destroy 2 in order to get Windows Defender to Start and run. I have now installed the old Spybot - Search & Destroy version 1.6.2 and now both applications are working properly. It appears that Spybot - Search & Destroy 2 conflicts with the default Windows Defender in Windows 8. I don't know if there are any solutions to this conflicting issue, but I will stay with Spybot - Search & Destroy version 1.6.2 for unless someone has a way to make things work properly.