Installed what? The only software I know of included on the CD is the toolbar and the Shareport program, neither which fit your description. As far as I know no software is needed, your computer just needs to be configured as a media server(available with most versions Vista, and almost all versions Windows 7), and your TV needs the ability to connect to that server. Perhaps your computer is configured different after re-installing the OS? Perhaps your newly install AV is blocking it? Unknown, but since you didn't change any settings on your router, I don't see how it could be a router issue. Wish you luck though.