I cant play ESF because some files is missing

When I activated ESF in the game, and create lan games, it says couldnt open library, and it points to some files named client_dll
Is it because that I am using Half Life Counterstrike and I can't play it?

Hey I use Counter-Strike and it works perfect

I suggest re-installing, and if that doesn't work try downloading the install from a different location.

Also someone else had this problem not long ago.