The file steamclient64.dll is a critical 64-bit dynamic link library used by the to handle core functions like connection management, inter-process communication, and Steamworks SDK features for games.
Go to your main Steam install (usually C:\Program Files (x86)\Steam ). Copy Files: Find steamclient64.dll and tier0_s64.dll . steamclient64.dll
Place them in your dedicated server's binary folder (e.g., .\Binaries\Win64\ for many Unreal Engine games). The file steamclient64