Jagdflieger - Don't know if I can answer that one, I use XPProSP3; however, I found using 7Zip is otherwise the answer to problems like this - I had problems with my downloaded zip file as well, with WinZip, but it opened fine with 7Zip and, once I was past the initial opening, I was able to install per normal methods. I'm planning on keeping the 7Zip on my desktop as an alternate method if these things fail to otherwise open properly in WinZip.