at.dll it is dynamic link library that is a part of Microsoft Visual C ++ component. It is used by many modern games and programs: pes 2016, Gta 5, far cry 4, Sims 4, Arma 3, Battlefield 4, Watch Dogs, Pes 2013 Dragon Age: Inquisition and many more.
Usually at.dll located at Windows \ System32 if you are running Windows 32 bit. If you are running Windows 64 bit (does not matter which one - XP, Vista, Seven or 8) copy of this file also located atWindows \ SysWOW64.
How to download free at.dll?
If at.dll is missing in one or both directories, program or game that uses this file can not find it and can not receive required data, so you get error like that:
Of course, you do not need to reinstall game or program. You just need to download at.dll and install it properly to fix this error.