I don't know what windows you are running but I think all of them have a built in extractor. You highlight the file right click an there should be an option of extract all files, In win7 I know when I open the file by clicking on it on the menu above asks if I want to extract files so I just click that option. Hope this helps
you could contact winzip or re load it,Do you have your contract no. i have winzip and I put it on both my computers all you need is your number it may not ask for it.But they are very good about contacting you back.contact technical support