Problems with Installation

I purchased Internet Security 2011 and tried to download it to upgrade my trial version that came with my laptop.  I followed the three step process per the web page but it stalled out at the installation (was stuck on 7% and never completed).  It did put a shortcut on my desktop called Norton Installation Files.  I went back to the Norton Download Manager and tried it again.  I got through step 2 but nothing downloaded or installed as far as I can tell.  Please advise how I can get it to download and install/upgrade my trial version.

 

Thanks