Guides: fixing DLL file errors
These guides explain, step by step, how to fix the most frequent DLL errors: which official solution to use, when to download a single file, and what to do if the error persists.
Visual C++ errors (msvcp, msvcr, vcruntime)
Fix msvcp140.dll, vcruntime140.dll, msvcr100.dll and other Visual C++ DLL errors: which package to install, 32-bit or 64-bit, and what to do if the error persists.
DirectX errors (d3dx9, xinput, d3dcompiler)
Why Windows 10 and 11 show d3dx9_43.dll, xinput1_3.dll or d3dcompiler_43.dll errors despite DirectX 12, and how to install Microsoft’s official DirectX components.
steam_api.dll error
steam_api.dll or steam_api64.dll missing, not found or “SteamAPI_Init failed”: verify the game files, the antivirus and Steam to fix the error.
unarc.dll / ISDone.dll error
Error “ISDone.dll: An error occurred when unpacking! Unarc.dll returned an error code” while installing a game: causes and step-by-step solutions.
Missing Windows system DLL
kernel32.dll, user32.dll, d3d9.dll, mfplat.dll…: repair a missing or damaged Windows system file with SFC, DISM and Windows Update, safely.
Error 0xc000007b (32-bit / 64-bit DLL)
Error 0xc000007b when starting a game or program: why it appears (32-bit and 64-bit DLLs mixed up) and how to fix it step by step on Windows 10 and 11.