I've installed Kaspersky Internet Security 2014 on both the Mac and on the Windows 8.1 install running inside the latest version of Parallels. Once I did, the Windows VM come to a complete grind (like when the CPU is at 100% usage), and I couldnt even swipe to Mac after seconds, and had to force shutdown the machine. On restart it did the same within a few minutes of use, even the login screen was terribly slow. I disabled Kaspersky on Mac firstly, uninstalled it off Windows and all was ok. I re-downloaded Kaspersky for Windows and installed, then same thing again once enabled it almost totally killed the machine. I disabled every protection in Kaspersky other than File protection on Windows, and it seems to improve things. I suspect having it on both the host and VM is causing a conflict, but with it being disabled on Mac that sort of throws that idea out of the window so it seems to be an issue with Windows inside Parallels running Kaspersky, but I found nothing on Google about the issue which I thought would be there if it was common. I'm running OS X 10.9.2 and Windows 8.1 with all current updates, and Parallels Build 9.0.24229, Kaspersky 14.0.0.4651 (d). Virtualization is enabled for Parallels in this Windows if that makes any difference, and the RAM is set to 12GB of the machines 16GB, and all 8 CPUs (I'm using a Macbook Pro Retina 15in Early 2013 512GB). Anyone got any ideas or had this issue themselves?