If you've been doing regular backups of your server, then restore to a point before you were infected by the virus. If not, you should reinstall Windows Home Server 2011. If you have no backups of your server at all, I would recommend making a copy of everything
except the system partition before the reinstallation.
One final piece of advice: in the future avoid using your server as a desktop PC, since it's unlikely your server was infected in any other way.
I'm not on the WHS team, I just post a lot. :)