Hi: My MacBook Pro (with Windows 7 Parallels Desktop) has been operating witout problems for several years. However, after downloading and installing the Kaspersky Anti-virus application included with the Mac OS, the system crashed, with the requisite message notation to reboot. I had previously downloaded and installed the Kaspersky Internet Security application, also included with the MacBookPro, apparently successfully. On attempting to reboot, the process proceeded only to the point of the Apple logo and the rotating circle being displayed, and seemingly freezing thereafter. That process was repeated, after awaiting five minutes with no apparent activity, via a hard power-down and power-up (after about one minute) via the power switch. The result was the same. The process was repeated a second time with the same result. The computer had to be powered off via the power switch. Please advise what may have happened, and, more importantly, what can be done to recover to proper operation of the MacBook Pro.