Someone please help!

I'm really new and need some help here. I'm sorry if this has been answered elsewhere, if it has, I haven't been able to find it. I have downloaded both the FilePlanet Beta 1.1 version and the Black-Plague Designs Steampack. I have tried to install both and have been unable to get either to work. The Steampack works, untill I try to get into a server. Then I get an error saying "Your .dll [cl_dlls\client.dll] differs from the server's". Can someone please tell me what I am doing wrong and how can I fix this? (P.S. Whenever I try to start a new game I have no maps in my map select and the game crashes.)

you probaly did somthing wrong but if you want ESF Steam download the ESF Steam install from esf world

(http://esf-world.com/download.php?file_id=475)

if not search the forums cause there is plenty on the client.dll