Step 2 of 6 Board up the window
The handful of checks that prevent almost every failed install.
Nearly every failed install traces back to one of four things: the wrong folder, a game that has never been launched, a half-extracted archive, or antivirus quietly removing a file. Five minutes here and none of those can happen to you.
The checklist
win-x64. There is no 32-bit path for this game — the shipped executable is 64-bit.v0.1d nazi zombies early access in the corner of the main menu..rarBoth mods ship as .rar, which Windows Explorer cannot open on its own. 7-Zip, NanaZip or WinRAR all work. The loader is a .zip and needs nothing extra.C:\Program Files (x86), Windows may ask for permission when you paste files in. Accept it.A different game build is usually fine
The mod resolves the game’s types by name at runtime rather than against a fixed offset, so a later hotfix normally keeps working. If a game update ever renames or removes something it needs, the mod reports it in the console and stands down to the stock AI for the level instead of breaking your run. Nothing silently half-works.
Step one of everything
Everything in this guide happens in one folder: the one that contains
Nazi Zombies.exe. If Steam is the only place you have ever launched the
game from, let Steam tell you where that is rather than guessing.
Right-click the game in the left-hand list.
Explorer opens directly in the game folder. This is the folder every instruction on this site calls the game root.
Before BepInEx is installed, the folder holds these. If you cannot see
Nazi Zombies.exe and Nazi Zombies_Data side by side, you are
in the wrong folder — most likely one level too high, in
steamapps\common.
A clean game root, before anything is installed
On the machine these screenshots were taken on, that folder is here. Yours will differ — the drive letter and library folder are whatever you chose when you installed Steam.
F:\SteamLibrary\steamapps\common\Nazi ZombiesC:\Program Files (x86)\Steam\steamapps\common\Nazi ZombiesDo not install into the Steam folder itself
steamapps\common is the folder that contains game folders. Files
dropped there do nothing at all, and it is the single most common way people end up with a
game that launches perfectly and loads no mods whatsoever.
The awkward part
BepInEx works by placing a file called winhttp.dll next to the game
executable. Windows loads it before the game’s own code runs, which is exactly the
foothold the loader needs — and also exactly the shape of a technique malware uses.
Some antivirus products flag it on that shape alone, without anything being wrong.
That is antivirus quarantine, not a bad download. Check its quarantine list, restore the file, and add the game folder to the exclusions before trying again. Verify the archive’s SHA-256 first if you would rather be certain of what you are restoring.
Expected. These archives are not code-signed and have no download reputation. Choose Keep, then check the checksum on the downloads page — that is a stronger guarantee than a signature anyway.
Right-click the downloaded archive, choose Properties, and if there is an Unblock checkbox at the bottom, tick it and apply before extracting. Windows otherwise marks every extracted file as foreign.
One thing genuinely worth being careful about
A loader like this runs arbitrary code inside your game. That is what makes it useful and it is also why where you get it from matters. Every archive on this site has a published SHA-256 checksum, and the BepInEx package is the upstream bleeding-edge build with a documented, verifiable addition. Check the hashes if you have any doubt at all — the downloads page shows you how in one command.
Reassurance, briefly
| Concern | What actually happens |
|---|---|
| Does it modify game files? | No. Every file it adds is new. GameAssembly.dll is read to build the interop layer and never written to. |
| Will Steam notice? | No. Steam tracks the files it shipped; it does not object to extra ones sitting alongside them. |
| Does verifying integrity remove it? | Normally not — verification restores missing or altered official files and leaves unknown extras alone. It is still worth re-checking the folder afterwards. |
| Will my saves survive? | Yes. savedata is untouched, and the mod never writes to it. |
| Can I remove it later? | Yes, completely, by deleting the folders you added. Full removal steps. |
| Is it safe in online co-op? | Yes. The zombie AI drives from the host and documents one honest engine boundary rather than hiding it (the co-op model); the mystery box is per-client and works even in a lobby where nobody else has it (why). |
| Do I have to install both mods? | No. They are completely independent — take either, both, or add the second one later without redoing anything. |
Next
You know where the game folder is, you can open a .rar, and your antivirus is
not going to eat the loader halfway through. Get the two archives next.