How to Fix “#include errors detected” in VS Code (C++)

Short answer: VS Code’s C/C++ extension can’t find the standard library headers, because it doesn’t know which compiler you’re using — or there isn’t one installed yet. Install a compiler, then point the extension at it with C/C++: Select IntelliSense Configuration. Don’t paste folders into includePath by hand.

You’ll usually see these two together, with a red squiggle under #include <iostream>:

#include errors detected. Please update your includePath. Squiggles are disabled for this translation unit
cannot open source file "iostream"

First: Does Your Code Actually Compile?

These errors come from IntelliSense — the editor’s live code checking — not from the compiler. They’re two separate things, so check which one is broken. Open the terminal in VS Code (Terminal → New Terminal) and compile:

g++ main.cpp -o main

• It compiles: your compiler works and only the editor is confused. Skip to Step 2.
• 'g++' is not recognized: there’s no working compiler yet. Fix that first — see how to fix ‘g++ is not recognized’ — then come back.

Step 1: Install a Compiler

VS Code is an editor. It doesn’t come with a C++ compiler, and IntelliSense needs one: it asks the compiler where the standard headers like iostream live.

After installing, quit VS Code completely and reopen it so it picks up the new compiler.

Step 2: Point the C/C++ Extension at Your Compiler

1. Press Ctrl+Shift+P (Cmd+Shift+P on a Mac) to open the Command Palette.
2. Type Select IntelliSense Configuration and choose C/C++: Select IntelliSense Configuration.
3. Pick your compiler from the list — for MinGW, the entry for g++.exe.

If you see a yellow Configure IntelliSense button in the status bar at the bottom, clicking it opens the same list.

If the list is empty, the extension couldn’t find a compiler. Make sure the compiler’s bin folder is on your PATH and reopen VS Code, or set the path by hand in Step 3.

Step 3: Or Set the Compiler Path by Hand

Open the Command Palette and run C/C++: Edit Configurations (UI). Find Compiler path and enter the full path to your compiler:

VS Code saves this in .vscode/c_cpp_properties.json inside your project folder. You can also edit that file directly (C/C++: Edit Configurations (JSON)). A working Windows version looks like this:

{
  "configurations": [
    {
      "name": "Win32",
      "includePath": ["${workspaceFolder}/**"],
      "compilerPath": "C:/msys64/ucrt64/bin/g++.exe",
      "cppStandard": "c++20",
      "intelliSenseMode": "windows-gcc-x64"
    }
  ],
  "version": 4
}

Use forward slashes in the path, or double every backslash (C:\\msys64\\...) — a single backslash isn’t valid in JSON.

Why You Shouldn’t Paste Folders into includePath

Plenty of old answers tell you to copy folders like .../lib/gcc/x86_64-w64-mingw32/13.2.0/include/c++ into includePath. That can work — until you update the compiler and the version number in the folder changes.

Microsoft’s documentation recommends against adding system include paths by hand for the compilers it supports. Set compilerPath instead, and the extension asks the compiler where its headers are.

includePath is for your own extra header folders, such as a library you downloaded. The default ${workspaceFolder}/** already covers every header inside your project.

Still Seeing Squiggles?

VS Code was open when you installed the compiler. Quit it completely and reopen it, or run Developer: Reload Window from the Command Palette.

The wrong compiler is selected. The extension may have picked a different compiler, such as Visual Studio’s cl.exe, or one you’ve since uninstalled. Run C/C++: Select IntelliSense Configuration again and choose the compiler you actually build with.

You opened a file instead of a folder. Use File → Open Folder on your project folder. The .vscode settings and ${workspaceFolder} only work when a folder is open.

The squiggle is only on your own header, like #include "player.h". That’s not a compiler problem. Check the spelling, check the file is in your project folder, and use quotes, not angle brackets, for your own headers. See header files in C++.

Using Visual Studio Instead?

Visual Studio (the full IDE, not VS Code) shows E1696 cannot open source file "iostream" when its C++ tools aren’t installed. The fix: open Visual Studio Installer, click Modify, tick Desktop development with C++, and install.

Quick Reference

Take Your C++ Further

Once VS Code is happy, the real learning starts. The C++ Better Explained Ebook takes you through the fundamentals in plain English, then the parts that trip beginners up most — pointers, memory and OOP. Just $19.

👉 Get the C++ Better Explained Ebook — $19

Related Articles

• How to Set Up C++ — install a compiler and VS Code, step by step.
• How to Fix ‘g++ is not recognized’ — when the terminal can’t find your compiler.
• How to Run a .cpp File — compile and run from VS Code or the terminal.
• Header Files in C++ — how #include works.
• Online C++ Compilers — code in your browser with nothing to configure.