vlk, Yeah it was 5.0.104. IceCube1010, I use Windows FW, Windows Defender and Zemana Antilogger. I don't think they may cause a conflict, but before installing avast! 5.0.104 I had already tested McAfee 2010 beta, AVG 9 beta and BitDefender 2010 haha. Although I had some uninstallation issues also with AVG and McAfee, I thought I cleaned the remnants well. OK, I'll admit that they might cause the CPU and slow down problem or Windows 7 might be the relevant issue. It'll be better if another Windows 7 user can state his/her experience (I don't wanna install it again). However, I saw some other people on some Turkish forums who are experiencing the same mail shield and web shield trouble (dunno what OS they use).