Rohan Blood Feud is currently out of Open Beta, which means there is a new client if you haven't already upgraded. If you have your Open Beta client, you need to download the new client or else you get an "Invalid Version" error. If you have never downloaded Rohan, these links will also help. This is not mandatory if you already downloaded it.
The following links are for the mirrors. Please pick one closest to your Location if you plan to download.
United States - West CoastEdit
United States - East CoastEdit