Operation Neptune Windows 11 Compatibility Patch

An unofficial, bring-your-own-files compatibility patch for the Windows version of Operation Neptune.

This repository contains no Operation Neptune game files and no copy of Microsoft's original WING32.DLL. You must supply files from your own original copy/install.

What it fixes

Version 1.0.1 applies the set of fixes tested against the supported 32-bit build:

• bypasses the obsolete 8-bit / 256-color startup requirement;
• makes the original WinG runtime usable as a local DLL instead of requiring installation in the Windows system directory;
• scales the original 640×400 game surface to 1280×800 using a tested 2× integer scaler;
• remaps mouse coordinates to the original 640×400 logical viewport;
• keeps the original gameplay, audio, timing, keyboard behavior, resources, and save format intact.

The patch does not emulate Windows 3.x. The original disc includes a full 32-bit ONWIN32.EXE, which this project patches for modern Windows.

Requirements

• Windows 11 or a comparable modern 64-bit Windows installation;
• the supported original ONWIN32.EXE and its original NEP*.DLL/SOUNDS data;
• the supported original WING32.DLL, or Microsoft's compressed WING32.DL_ form, from an original WinG installation/package.

Supported hashes are documented in docs/TECHNICAL.md. Unknown builds are rejected instead of being patched blindly.

Quick start

1. Download the release ZIP and extract it somewhere temporary.
2. Double-click NeptunePatch.cmd.
3. Select your original Operation Neptune CD/extracted-CD folder (or another folder containing the original ONWIN32.EXE).
4. If the patcher cannot find WinG under that folder, select either the original WING32.DLL or its Microsoft-compressed WING32.DL_ form when prompted. WING32.DL_ is expanded automatically with Windows expand.exe.
5. Choose where the new patched installation should be created.
6. Run Play Operation Neptune.cmd from the generated game folder.

The patcher never modifies the source copy. It creates a new installation from your original files and applies the compatibility changes only to the copies.

Command-line use

.\NeptunePatch.ps1 `
  -Source "D:\" `
  -Wing32 "C:\OldWinG\WING32.DL_" `
  -Destination "C:\Games\Operation Neptune"

-Wing32 can be omitted if a matching WING32.DLL or tested WING32.DL_ exists somewhere under -Source.

Where do I get WinG?

Modern Windows does not normally contain this old WinG runtime. The patcher accepts either:

• WING32.DLL — the installed 32-bit WinG runtime; or
• WING32.DL_ — Microsoft's old SZDD-compressed form of that DLL.

If you provide WING32.DL_, the patcher uses Windows' built-in expand.exe, then verifies that the expanded DLL matches the supported SHA-256 before patching it.

The Operation Neptune CD used during development contains a WING.Z WinG installer archive, not a loose WING32.DLL. Version 1.0.1 detects WING.Z and explains this, but does not yet unpack the InstallShield .Z archive automatically. You can instead supply WING32.DLL/WING32.DL_ from your own original WinG installation or extracted WinG package.

Do not download random copies from DLL aggregation sites; unknown WinG builds are rejected anyway.

Why a patcher instead of a prepatched game?

The release contains only original compatibility code, patch metadata, and documentation. The user supplies all copyrighted game/runtime files. The patcher verifies known SHA-256 hashes before changing anything and refuses unexpected versions.

Supported build

The initial release supports the specific 32-bit Operation Neptune build used during development. If you own a different legitimate release and the patcher rejects it, please open an issue with:

• the filename;
• file size;
• SHA-256 hash;
• release/edition information you know.

Do not upload the copyrighted executable or game data to an issue.

Project scope

The goal is compatibility, not gameplay modification. The patch aims to reproduce the original game behavior on a modern Windows desktop while keeping the original data and logic intact.

License and rights

The compatibility patcher and original scaler code in this repository are released under the MIT License. That license applies only to code authored for this project.

Operation Neptune, its original executables, graphics, audio, data, and related intellectual property belong to their respective rights holders. WING32.DLL is third-party Microsoft software and is not included. This project is unofficial and unaffiliated with The Learning Company, Microsoft, or their successors.