I installed a new hard drive on my Mac OS X 10.8.2, so I directly installed the latest version of Parallels Desktop 8 (8.0.18345). The problem is solved! So it seems that a fresh install solves the problem. It probably means that Parallels Desktop or Mac OS X leaves something in the system which causes this problem, because I had Mac OS X 10.8 on top of 10.7 and Parallels Desktop 8 on top of 7. I hope it helps. Fra
I have the opposite problem - I only use Windows with Parallels, and, being a heavy keyboard user, I want to have BOTH Alt keys be Alt keys. I have no use for the Ctrl/Alt combination. Seems like this should be an option that we can configure...