Zandronum

I can't join a server.

I get a error message that says " Cilent binary cannot be obtained for game zandronum executable for zandronum cilent: C:/New Folder/zandronum.exe is a directory or doesn't exist"

Doomseeker is not configured correctly. You must show it where your game is installed in configuration box. When you install Zandronum with Doomseeker then Doomseeker should already be configured properly so I guess you must have moved the game somewhere else and that's why you get the error.