virtualbox.org

i had installed VirtualBox-3.0.2-49928-Win.exe on my system then i uninstalled because of some reason
now if i try to install it again it is crashing with no errors.
a window with "installing" text comes and then the window disappears.
i even tried VirtualBox-3.0.4-50677-Win.exe same result

Try running this from Microsoft http://support.microsoft.com/kb/290301 before you run the install again.