Steam tells me that there is something wrong with my network or with Steamworks. I only get the try it now "bot" for a response with no relief.
My game rig is high end running win7 64 and I also had total war napoleon which worked for a while. My play is mainly offline and when I update windows occasionally I also update all other programs as well; for example: Firefox 21 to 24. Steam has always been difficult but now will not work at all. I hope this gives you a shot at figuring out how to use steam. By the Way there are no mods used.