MSBuild regression: process environment contains both PATH and Path
Resolved 💬 2 comments Opened Jun 13, 2026 by tom-huntington Closed Jun 13, 2026
What version of Codex CLI is running?
codex-cli 0.139.0
What subscription do you have?
Plus
Which model were you using?
gpt-5.5
What platform is your computer?
Microsoft Windows NT 10.0.26200.0 x64
What terminal emulator and version are you using (if applicable)?
Windows Terminal PowerShell
Codex doctor report
<details>
<summary>json</summary>
{
"schemaVersion": 1,
"generatedAt": "1781322078s since unix epoch",
"overallStatus": "ok",
"codexVersion": "0.139.0",
"checks": {
"app_server.status": {
"id": "app_server.status",
"category": "app-server",
"status": "ok",
"summary": "background server is not running",
"details": {
"control socket": "C:\\Users\\tynda\\.codex\\app-server-control\\app-server-control.sock",
"daemon state dir": "C:\\Users\\tynda\\.codex\\app-server-daemon",
"mode": "ephemeral",
"pid file": "C:\\Users\\tynda\\.codex\\app-server-daemon\\app-server.pid (missing)",
"settings": "C:\\Users\\tynda\\.codex\\app-server-daemon\\settings.json (missing)",
"status": "not running",
"update-loop pid file": "C:\\Users\\tynda\\.codex\\app-server-daemon\\app-server-updater.pid (missing)"
},
"remediation": null,
"durationMs": 0
},
"auth.credentials": {
"id": "auth.credentials",
"category": "auth",
"status": "ok",
"summary": "auth is configured",
"details": {
"auth file": "C:\\Users\\tynda\\.codex\\auth.json",
"auth storage mode": "File",
"stored API key": "false",
"stored ChatGPT tokens": "true",
"stored agent identity": "false",
"stored auth mode": "chatgpt"
},
"remediation": null,
"durationMs": 0
},
"config.load": {
"id": "config.load",
"category": "config",
"status": "ok",
"summary": "config loaded",
"details": {
"CODEX_HOME": "C:\\Users\\tynda\\.codex",
"config.toml": "C:\\Users\\tynda\\.codex\\config.toml",
"config.toml parse": "ok",
"cwd": "C:\\Users\\tynda",
"enabled feature flags": "shell_tool, shell_snapshot, terminal_resize_reflow, sqlite, hooks, enable_request_compression, multi_agent, apps, tool_suggest, plugins, in_app_browser, browser_use, browser_use_external, computer_use, plugin_sharing, image_generation, skill_mcp_dependency_install, steer, guardian_approval, goals, collaboration_modes, tool_call_mcp_elicitation, personality, fast_mode, tui_app_server, workspace_dependencies",
"feature flag overrides": "none",
"feature flags enabled": "26",
"log dir": "C:\\Users\\tynda\\.codex\\log",
"mcp servers": "0",
"model": "gpt-5.5",
"model provider": "openai",
"sqlite home": "C:\\Users\\tynda\\.codex"
},
"remediation": null,
"durationMs": 0
},
"git.environment": {
"id": "git.environment",
"category": "git",
"status": "ok",
"summary": "git version 2.52.0.windows.1",
"details": {
"PATH git #1": "C:\\Program Files\\Git\\cmd\\git.exe",
"PATH git entries": "1",
"git build options": "git version 2.52.0.windows.1; cpu: x86_64; built from commit: 2912d8e9b8253723974b7baf1c890273b1a1c5bd; sizeof-long: 4; sizeof-size_t: 8; shell-path: D:/git-sdk-64-build-installers/usr/bin/sh; rust: disabled; feature: fsmonitor--daemon; libcurl: 8.17.0; OpenSSL: OpenSSL 3.5.4 30 Sep 2025; zlib: 1.3.1; SHA-1: SHA1_DC; SHA-256: SHA256_BLK; default-ref-format: files; default-hash: sha1",
"git exec path": "C:/Program Files/Git/mingw64/libexec/git-core",
"git version": "git version 2.52.0.windows.1",
"repo detected": "false",
"selected git": "C:\\Program Files\\Git\\cmd\\git.exe"
},
"remediation": null,
"durationMs": 35
},
"installation": {
"id": "installation",
"category": "install",
"status": "ok",
"summary": "installation looks consistent",
"details": {
"PATH codex #1": "C:\\Users\\tynda\\AppData\\Roaming\\npm\\codex",
"PATH codex #2": "C:\\Users\\tynda\\AppData\\Roaming\\npm\\codex.cmd",
"PATH codex entries": "2",
"current executable": "C:\\Users\\tynda\\AppData\\Roaming\\npm\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\bin\\codex.exe",
"install context": "npm (package C:\\Users\\tynda\\AppData\\Roaming\\npm\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc, bin C:\\Users\\tynda\\AppData\\Roaming\\npm\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\bin, resources C:\\Users\\tynda\\AppData\\Roaming\\npm\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\codex-resources, path C:\\Users\\tynda\\AppData\\Roaming\\npm\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\codex-path)",
"managed by bun": "false",
"managed by npm": "true",
"managed package root": "C:\\Users\\tynda\\AppData\\Roaming\\npm\\node_modules\\@openai\\codex",
"npm update target": "C:\\Users\\tynda\\AppData\\Roaming\\npm\\node_modules\\@openai\\codex"
},
"remediation": null,
"durationMs": 286
},
"mcp.config": {
"id": "mcp.config",
"category": "mcp",
"status": "ok",
"summary": "no MCP servers configured",
"details": {},
"remediation": null,
"durationMs": 0
},
"network.env": {
"id": "network.env",
"category": "network",
"status": "ok",
"summary": "network-related environment looks readable",
"details": {
"proxy env vars": "none"
},
"remediation": null,
"durationMs": 0
},
"network.provider_reachability": {
"id": "network.provider_reachability",
"category": "reachability",
"status": "ok",
"summary": "active provider endpoints are reachable over HTTP",
"details": {
"ChatGPT base URL": "https://chatgpt.com/backend-api/ reachable (HTTP 403)",
"reachability mode": "ChatGPT auth"
},
"remediation": null,
"durationMs": 142
},
"network.websocket_reachability": {
"id": "network.websocket_reachability",
"category": "websocket",
"status": "ok",
"summary": "Responses WebSocket handshake succeeded",
"details": {
"DNS": "2 IPv4, 2 IPv6, first IPv6",
"auth mode": "chatgpt",
"connect timeout": "15000 ms",
"endpoint": "wss://chatgpt.com/backend-api/<redacted>",
"handshake result": "HTTP 101 Switching Protocols",
"model provider": "openai",
"models etag present": "true",
"provider name": "OpenAI",
"proxy env vars": "none",
"reasoning header": "false",
"server model present": "false",
"supports websockets": "true",
"wire API": "responses"
},
"remediation": null,
"durationMs": 538
},
"runtime.provenance": {
"id": "runtime.provenance",
"category": "runtime",
"status": "ok",
"summary": "running npm on windows-x86_64",
"details": {
"commit": "unknown",
"current executable": "C:\\Users\\tynda\\AppData\\Roaming\\npm\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\bin\\codex.exe",
"install method": "npm (package C:\\Users\\tynda\\AppData\\Roaming\\npm\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc, bin C:\\Users\\tynda\\AppData\\Roaming\\npm\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\bin, resources C:\\Users\\tynda\\AppData\\Roaming\\npm\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\codex-resources, path C:\\Users\\tynda\\AppData\\Roaming\\npm\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\codex-path)",
"platform": "windows-x86_64",
"version": "0.139.0"
},
"remediation": null,
"durationMs": 0
},
"runtime.search": {
"id": "runtime.search",
"category": "search",
"status": "ok",
"summary": "search is OK (bundled)",
"details": {
"search command": "C:\\Users\\tynda\\AppData\\Roaming\\npm\\node_modules\\@openai\\codex\\node_modules\\@openai\\codex-win32-x64\\vendor\\x86_64-pc-windows-msvc\\codex-path\\rg.exe",
"search command readiness": "file exists",
"search provider": "bundled"
},
"remediation": null,
"durationMs": 0
},
"sandbox.helpers": {
"id": "sandbox.helpers",
"category": "sandbox",
"status": "ok",
"summary": "sandbox configuration is readable",
"details": {
"approval policy": "OnRequest",
"codex-linux-sandbox helper": "none",
"execve wrapper helper": "none",
"filesystem sandbox": "restricted",
"network sandbox": "restricted"
},
"remediation": null,
"durationMs": 0
},
"state.paths": {
"id": "state.paths",
"category": "state",
"status": "ok",
"summary": "state paths and databases are inspectable",
"details": {
"CODEX_HOME": "C:\\Users\\tynda\\.codex (dir)",
"active rollout files": "682 files, 104883170 total bytes, 153787 average bytes",
"archived rollout files": "0 files, 0 total bytes, 0 average bytes",
"goals DB": "C:\\Users\\tynda\\.codex\\goals_1.sqlite (file)",
"goals DB integrity": "ok",
"log DB": "C:\\Users\\tynda\\.codex\\logs_2.sqlite (file)",
"log DB integrity": "ok",
"log dir": "C:\\Users\\tynda\\.codex\\log (dir)",
"memories DB": "C:\\Users\\tynda\\.codex\\memories_1.sqlite (file)",
"memories DB integrity": "ok",
"sqlite home": "C:\\Users\\tynda\\.codex (dir)",
"state DB": "C:\\Users\\tynda\\.codex\\state_5.sqlite (file)",
"state DB integrity": "ok"
},
"remediation": null,
"durationMs": 1434
},
"state.rollout_db_parity": {
"id": "state.rollout_db_parity",
"category": "threads",
"status": "ok",
"summary": "rollout files and state DB thread inventory agree",
"details": {
"default model provider": "openai",
"rollout DB active files": "682",
"rollout DB active rows": "682",
"rollout DB archive mismatches": "0",
"rollout DB archived files": "0",
"rollout DB archived rows": "0",
"rollout DB duplicate DB paths": "0",
"rollout DB duplicate rollout thread ids": "0",
"rollout DB malformed file names": "0",
"rollout DB missing active rows": "0",
"rollout DB missing archived rows": "0",
"rollout DB model providers": "openai=682",
"rollout DB rows": "682",
"rollout DB scan cap reached": "false",
"rollout DB scan errors": "0",
"rollout DB sources": "cli=661, subagent:thread_spawn=21",
"rollout DB stale rows": "0"
},
"remediation": null,
"durationMs": 5092
},
"system.environment": {
"id": "system.environment",
"category": "system",
"status": "ok",
"summary": "OS language en-GB",
"details": {
"EDITOR": "not set",
"VISUAL": "not set",
"os": "Windows 10.0.26200 (Windows 11 Core) [64-bit]",
"os language": "en-GB",
"os type": "Windows",
"os version": "10.0.26200"
},
"remediation": null,
"durationMs": 0
},
"terminal.env": {
"id": "terminal.env",
"category": "terminal",
"status": "ok",
"summary": "terminal metadata was detected",
"details": {
"WT_SESSION": "present",
"color output": "enabled",
"console input code page": "850",
"console output code page": "850",
"stderr console mode": "0x00000007 (VT processing: true)",
"stderr is terminal": "true",
"stdin is terminal": "true",
"stdout console mode": "0x00000007 (VT processing: true)",
"stdout is terminal": "true",
"terminal": "Windows Terminal",
"terminal size": "116x30"
},
"remediation": null,
"durationMs": 0
},
"terminal.title": {
"id": "terminal.title",
"category": "title",
"status": "ok",
"summary": "terminal title default",
"details": {
"terminal title activity": "true",
"terminal title items": "activity, project-name",
"terminal title project source": "cwd",
"terminal title project value": "tynda",
"terminal title source": "default"
},
"remediation": null,
"durationMs": 0
},
"updates.status": {
"id": "updates.status",
"category": "updates",
"status": "ok",
"summary": "update configuration is locally consistent",
"details": {
"cached latest version": "0.139.0",
"check for update on startup": "true",
"last checked at": "2026-06-13T03:14:27.018794900Z",
"latest version": "0.139.0",
"latest version status": "current version is not older",
"npm update target": "C:\\Users\\tynda\\AppData\\Roaming\\npm\\node_modules\\@openai\\codex",
"update action": "npm install -g @openai/codex",
"version cache": "C:\\Users\\tynda\\.codex\\version.json"
},
"remediation": null,
"durationMs": 2076
}
}</details>
What issue are you seeing?
Codex can't run my build command. Codex found a workaround by using Remove-Item Env:PATH
Codex reasoning
The build did not reach the C++ compile: MSBuild failed before invoking CL.exe because the process environment contains both PATH and Path. I’m going to rerun the same build from a cleaned environment for this process so we can get real compiler feedback.
$ Remove-Item Env:PATH -ErrorAction SilentlyContinue; msbuild App.sln /p:Configuration=Debug / p:Platform=x64 -nologo -clp:ErrorsOnlyError message:
$ msbuild App.sln /p:Configuration=Debug /p:Platform=x64 -nologo -clp:ErrorsOnly C:\Program Files\Microsoft Visual Studio\18\Community\MSBuild\Microsoft\VC\v180\Microsoft.CppCommon.targets(790,5):
error MSB6001: Invalid command line switch for "CL.exe". System.ArgumentException: Item has already been added. Key in dictionary: 'PATH' Key being added: 'Path' [C:
\Users\tynda\App\App.vcxproj]
C:\Program Files\Microsoft Visual Studio\18\Community\MSBuild\Microsoft\VC\v180\Microsoft.CppCommon.targets(790,5):
error MSB6001: at System.Collections.Hashtable.Insert(Object key, Object nvalue, Boolean add) [C: \Users\tynda\App\AppS.vcxproj]
C:\Program Files\Microsoft Visual Studio\18\Community\MSBuild\Microsoft\VC\v180\Microsoft.CppCommon.targets(790,5): error MSB6001: at System.Diagnostics.ProcessStartInfo.get_EnvironmentVariables() [C:
\Users\tynda\App\App.vcxproj]
C:\Program Files\Microsoft Visual Studio\18\Community\MSBuild\Microsoft\VC\v180\Microsoft.CppCommon.targets(790,5):
error MSB6001: at Microsoft.Build.Utilities.ToolTask.GetProcessStartInfo(String pathToTool, String commandLineCommands, String responseFileSwitch) [C:
\Users\tynda\App\App.vcxproj] C:\Program Files\Microsoft Visual Studio\18\Community\MSBuild\Microsoft\VC\v180\Microsoft.CppCommon.targets(790,5):
error MSB6001: at Microsoft.Build.Utilities.ToolTask.ExecuteTool(String pathToTool, String responseFileCommands, String commandLineCommands) [C:\Users\tynda\App\App.vcxproj]
C:\Program Files\Microsoft Visual Studio\18\Community\MSBuild\Microsoft\VC\v180\Microsoft.CppCommon.targets(790,5):
error MSB6001: at Microsoft.Build.CPPTasks.TrackedVCToolTask.TrackerExecuteTool(String pathToTool, String
responseFileCommands, String commandLineCommands) [C:
\Users\tynda\App\App.vcxproj]
C:\Program Files\Microsoft Visual Studio\18\Community\MSBuild\Microsoft\VC\v180\Microsoft.CppCommon.targets(790,5):What steps can reproduce the bug?
The build works if I run it with a bang command. Only errors when codex runs the build.
If you create a WinUI3 starter template, you should be able to repo.
What is the expected behavior?
_No response_
Additional information
_No response_
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