I've been having a problem with Windows 8 and other MSFT programs when running Widows via parallels. I have a legal copy of both Windows and Parallels 9, but after 30 minutes of using Windows via Parallels, Windows prompts me to authorize my copy of Windows and say that my copy is not valid. This issue doesn't occur when I boot into the Windows partition. It only happens with parallels. When the prompt happens, the system lags and become less responsive. I really like using Parallels, but I want to fix this issue. Any ideas? Thanks!