What does error 0xc000007b mean in Killing Floor 2?

Windows could not load the game because a required DLL is missing, damaged or the wrong bitness (32-bit vs 64-bit). In practice it almost always points to Visual C++ runtime files.

Which Visual C++ packages should I install?

Install both the x86 and x64 Microsoft Visual C++ Redistributable from Microsoft (aka.ms/vs/17/release/vc_redist.x86.exe and vc_redist.x64.exe). Having both is normal and harmless.

Steam shows 'Running' for two seconds and then goes back to 'Play'. Is that the same problem?

Often yes. When launched through Steam the game may close silently instead of showing the 0xc000007b box. Install the runtimes, restart, and check Event Viewer for the failing module.

I reinstalled Windows and it still fails. Why?

A fresh Windows install lacks many runtimes and drivers. Run Windows Update fully, install your GPU vendor's driver, then install the Visual C++ packages and try again.

Fixes & Performance

Killing Floor 2 Error 0xc000007b - How to Fix It

A player on r/killingfloor had just bought Killing Floor 2 on Steam and could not get it to start at all. Running the exe as administrator showed error 0xc000007b, and launching from Steam did nothing visible: the Play button changed to "Running" for about two seconds and then went back to "Play". Verifying files, reinstalling the game and even reinstalling Windows 10 did not help, on a modern PC (Ryzen 5 5600X, RX 6500 XT, 32 GB RAM, SSD). This page turns the community replies into a step-by-step fix. For other launch problems, see KF2 won't start: fixes from the official Steam thread.

What 0xc000007b means

The full message is usually "The application was unable to start correctly (0xc000007b)". It is a Windows loader error: the game asked for a DLL that is missing, broken, or built for the wrong architecture (a 32-bit DLL where a 64-bit one is expected, or the reverse). It is not a hardware problem, so a strong PC does not protect you from it. The usual culprits are the Microsoft Visual C++ runtimes, followed by .NET and older DirectX files.

Fix 1: install Visual C++ Redistributable, both x86 and x64

This was the main answer in the thread, given by several people. Install both versions of the current Microsoft Visual C++ Redistributable:

x86 (32-bit): https://aka.ms/vs/17/release/vc_redist.x86.exe
x64 (64-bit): https://aka.ms/vs/17/release/vc_redist.x64.exe

Having both installed is normal; many programs need the 32-bit one even on 64-bit Windows. If the installer offers Repair, use it. Restart the PC after installing, then launch KF2 from Steam.

Fix 2: .NET Framework and DirectX

Replies also suggested checking these:

.NET Framework. Make sure .NET Framework 3.5 is enabled in "Turn Windows features on or off" (Win+R, optionalfeatures), and that Windows Update has installed the current 4.x version.
DirectX. Windows 10 and 11 include DirectX 11 and 12, but some games still use older DirectX helper libraries that only come with Microsoft's legacy DirectX End-User Runtime. Installing it does not downgrade anything.

Normally Steam installs these packages on the first launch of a game. If that step was skipped or failed, you get exactly this kind of error.

Fix 3: after a clean Windows install

The player in the thread had reinstalled Windows, which can make things worse rather than better. A fresh system is missing runtimes and proper drivers. Before testing the game again:

Run Windows Update until no more updates are offered (restart as needed).
Install the latest GPU driver from AMD, NVIDIA or Intel, not just the basic Windows one.
Install the Visual C++ packages from Fix 1.
Restart and try again.

Fix 4: find the exact failing file in Event Viewer

If the game still closes after two seconds, Windows has probably logged the reason:

Press Win+R, type eventvwr and press Enter.
Go to Windows Logs > Application.
Look for an Error entry at the time you pressed Play, mentioning KFGame.exe.
Check the faulting module name. A file like MSVCP140.dll or VCRUNTIME140.dll points to Visual C++, a d3dx or xinput file points to DirectX.

That name tells you which package to reinstall instead of guessing.

Fix 5: missing files in the game folder

One reply simply said that files were missing in the exe folder. Verifying the game in Steam (right-click the game > Properties > Installed Files > Verify integrity) restores the game's own files. Also check that your antivirus has not quarantined anything from the KF2 folder, and add an exclusion if it did.

Quick checklist

Step	Done?
Visual C++ Redistributable x86 + x64 installed, PC restarted
.NET Framework 3.5 enabled, Windows fully updated
GPU driver from the vendor installed
Legacy DirectX End-User Runtime installed
Event Viewer checked for the faulting module
Game files verified, antivirus quarantine checked

FAQ

What does error 0xc000007b mean in Killing Floor 2?: Windows could not load the game because a required DLL is missing, damaged or the wrong bitness (32-bit vs 64-bit). In practice it almost always points to Visual C++ runtime files.
Which Visual C++ packages should I install?: Install both the x86 and x64 Microsoft Visual C++ Redistributable from Microsoft (aka.ms/vs/17/release/vc_redist.x86.exe and vc_redist.x64.exe). Having both is normal and harmless.
Steam shows 'Running' for two seconds and then goes back to 'Play'. Is that the same problem?: Often yes. When launched through Steam the game may close silently instead of showing the 0xc000007b box. Install the runtimes, restart, and check Event Viewer for the failing module.
I reinstalled Windows and it still fails. Why?: A fresh Windows install lacks many runtimes and drivers. Run Windows Update fully, install your GPU vendor's driver, then install the Visual C++ packages and try again.