Microsoft Visual C++ isuses

Hi Geff,

I don't think it is a DLL-registration issue. I think there are two separate problems based on your post

1. VC++ runtime dependency . Particularly msvcp120.dll
2. vulcan module i.e vulcan_JIT must be enabled

msvcp120.dll is not a COM DLL and must not be registered. That's for sure. Install correct VC++ redistributable. That should work. The Assertion is your app complaining about its own config.

Care has to be taken with interpreting these errors. This is a case where it is an error that is being reported by the Visual C++ runtime and not originating from the runtime. To give an example:

#include <Windows.h>
#include <cassert>

int APIENTRY wWinMain(_In_ HINSTANCE, _In_opt_ HINSTANCE, _In_ LPWSTR, _In_ int)
{
	assert(false);

	MSG msg{};
	while (GetMessageW(&msg, nullptr, 0, 0))
	{
		DispatchMessageW(&msg);
	}

	return 0;
}

This shows:

It is the line assert(false) in my sample that is triggering this window.

The assertation indicates that you really should be looking at that node-vulcan or whatever. It seems like it has been built correctly, or you have not satisfied all dependencies for this library.

Thank you for reaching out.

The error message:

Expression: vulcan_JIT must be enabled

indicates that the application in use (associated with node-vulcan) requires a specific environment variable (VULCAN_JIT) to be enabled. This is not related to Windows or graphics drivers, but rather a configuration check within the application itself.

Attempts to unregister MSVCP120.dll were unnecessary, as this DLL is part of the Microsoft Visual C++ 2013 Redistributable and is managed by the official installer. Manual intervention with this file is not recommended and may lead to unintended issues.

Workarounds (Easy Steps to Try)

Step 1 – Quick Test via Command Prompt (Temporary)

1. Press Windows Key, type cmd, right-click Command Prompt → Run as administrator.
2. Navigate to your program’s folder, for example:

cd C:\path\to\node-vulcan\build\release

(Tip: If you’re not sure where it’s installed, check the project’s documentation.)

1. Run this command to enable the required setting:

set VULCAN_JIT=1

1. Then launch your program (e.g., yourapp.exe or npm start).

Note: This setting only lasts for that command prompt session.

Step 2 – Make It Permanent

If Step 1 worked, you can set this system-wide so you don’t need to type it every time:

1. Press Windows Key, type Environment Variables, and choose Edit the system environment variables.
2. In the System Properties window, click Environment Variables…
3. Under System variables, click New…
   • Variable name: VULCAN_JIT
     • Variable value: 1
     1. Save, close, and restart your computer.

Step 3 – Repair Visual C++ Redistributable (Only If Still Failing)

If you previously tried to unregister DLLs, your runtime may need repair.

1. Download the Visual C++ 2013 Redistributable (both x86 and x64) from Microsoft’s official site:
   https://free.blessedness.top/en-us/cpp/windows/latest-supported-vc-redist
2. Run the installer and choose Repair (or Install if missing).
3. Restart your PC.

Summary

• Main cause: Program needs VULCAN_JIT=1.
• Fix: Set this environment variable (first test temporarily, then make it permanent).
• If you previously altered DLLs: Repair the VC++ 2013 Redistributable.
• No need to uninstall all Redistributables, update GPU drivers, or register DLLs.

Let me know if you need any further help with this. We'll be happy to assist.

If you find this helpful, please mark this as answered.