: The .rar file (like the one you mentioned) is downloaded and extracted. It contains modified Steam API files (e.g., steam_api64.dll ).
: For deeper issues, you can run a command prompt as administrator and use: "C:\Program Files (x86)\Steam\bin\SteamService.exe" /repair . itb-fix-repair-steam-generic-4-rar
If you are looking to repair a Steam installation that is broken, the "story" is much simpler and uses official tools: steam_api64.dll ). : For deeper issues
Are you having trouble with a not launching, or are you trying to get multiplayer working on a custom build? go to Properties > Installed Files
: Right-click your game in the Steam Library, go to Properties > Installed Files , and select Verify integrity of game files .