Codex Desktop fails to open an already-running IntelliJ IDEA instance on Windows

[xuMingHai1]

What version of the Codex App are you using (From “About Codex” dialog)?

26.623.5546.0

What subscription do you have?

plus

What platform is your computer?

Microsoft Windows 11 Pro, version 10.0.26200, build 26200, 64-bit

What issue are you seeing?

When Codex Desktop is configured to open files/projects with IntelliJ IDEA by selecting idea64.exe, opening a project from Codex fails if IntelliJ IDEA is already running. Codex reports that idea64.exe exited with code 6. IDEA shows a startup error:

com.intellij.platform.ide.bootstrap.DirectoryLock$CannotActivateException:
Process "C:\Program Files\JetBrains\IntelliJ IDEA 2026.1.2\bin\idea64.exe" (4116)
is still running and does not respond.

The existing IDEA process is actually responsive. The issue appears to be in how Codex Desktop launches the GUI editor process, not in IDEA being genuinely hung.

What steps can reproduce the bug?

1. Start IntelliJ IDEA normally.
2. Open the project C:\dev\IdeaProjects\m3u8-downloader.
3. In Codex Desktop, choose IntelliJ IDEA as the file/project opener by selecting:
   C:\Program Files\JetBrains\IntelliJ IDEA 2026.1.2\bin\idea64.exe.
4. From Codex Desktop, open the same project/path in IDEA.

What is the expected behavior?

Codex should ask the already-running IDEA instance to open/focus the requested project or file, then return success.

Additional information

Bug report: Codex Desktop fails to open an already-running IntelliJ IDEA instance on Windows

Product

• Product: Codex Desktop for Windows
• Codex package: OpenAI.Codex_26.623.5546.0_x64__2p2nqsd0c76g0
• Codex version: 26.623.5546.0
• OS: Microsoft Windows 11 Pro, version 10.0.26200, build 26200, 64-bit

External editor

• Editor: IntelliJ IDEA 2026.1.2
• Executable: C:\Program Files\JetBrains\IntelliJ IDEA 2026.1.2\bin\idea64.exe
• JetBrains Runtime: 25.0.3+1-b329.124
• Existing IDEA process at the time of failure: idea64.exe PID 4116
• Existing IDEA main window was responsive and showing the project m3u8-downloader

Summary

When Codex Desktop is configured to open files/projects with IntelliJ IDEA by selecting idea64.exe, opening a project from Codex fails if IntelliJ IDEA is already running. Codex reports that idea64.exe exited with code 6. IDEA shows a startup error:

com.intellij.platform.ide.bootstrap.DirectoryLock$CannotActivateException:
Process "C:\Program Files\JetBrains\IntelliJ IDEA 2026.1.2\bin\idea64.exe" (4116)
is still running and does not respond.

The existing IDEA process is actually responsive. The issue appears to be in how Codex Desktop launches the GUI editor process, not in IDEA being genuinely hung.

Steps to reproduce

1. Start IntelliJ IDEA normally.
2. Open the project C:\dev\IdeaProjects\m3u8-downloader.
3. In Codex Desktop, choose IntelliJ IDEA as the file/project opener by selecting:
   C:\Program Files\JetBrains\IntelliJ IDEA 2026.1.2\bin\idea64.exe.
4. From Codex Desktop, open the same project/path in IDEA.

Expected result

Codex should ask the already-running IDEA instance to open/focus the requested project or file, then return success.

Actual result

Codex starts a second idea64.exe process, which fails during IntelliJ's single-instance DirectoryLock / Unix domain socket activation path. Codex logs:

[electron-fetch-handler] Failed to open file
errorMessage="C:\Program Files\JetBrains\IntelliJ IDEA 2026.1.2\bin\idea64.exe exited with code 6 (C:\dev\IdeaProjects\m3u8-downloader)"

The user-facing IDEA error includes suppressed socket errors:

Suppressed: java.net.SocketException: Invalid argument: bind
Suppressed: java.net.SocketException: Invalid argument: connect

Diagnostics already performed

• Existing IDEA process PID 4116 was responsive.
• Existing IDEA process and Codex were running under the same Windows user and same elevation level.
• IDEA lock files were consistent:
  • config lock file .lock pointed to PID 4116
  • system .port file behaved like a valid Windows Unix domain socket
• A Java probe was able to connect to IDEA's real .port socket.
• Running the same IDEA executable through PowerShell Start-Process succeeded and returned exit code 0.
• Reproducing Codex-like behavior with Node.js child_process.spawn() caused a second hidden idea64.exe process to appear, matching Codex Desktop's apparent launch pattern.

Relevant local Codex log

%LOCALAPPDATA%\Packages\OpenAI.Codex_2p2nqsd0c76g0\LocalCache\Local\Codex\Logs\2026\06\29\codex-desktop-14fa9bf7-86a8-48ee-9e8d-369aa507b788-6976-t0-i1-021018-0.log

Relevant entry:

2026-06-29T02:49:22.062Z error [electron-fetch-handler] Failed to open file
errorMessage="C:\Program Files\JetBrains\IntelliJ IDEA 2026.1.2\bin\idea64.exe exited with code 6 (C:\dev\IdeaProjects\m3u8-downloader)"

Suspected cause

Codex Desktop appears to launch the selected editor executable as an Electron/Node child process and waits for the process exit code. This launch method does not behave the same as ShellExecute / Start-Process for JetBrains GUI launchers. With IntelliJ IDEA already running, the child process can fail in IntelliJ's single-instance activation path and return exit code 6.

Recommended implementation direction: for GUI editor openers on Windows, use a ShellExecute-style detached launch, or spawn with detached/no inherited stdio semantics and do not treat the long-running GUI launcher process as the success condition.

Workaround

Using a wrapper that calls Start-Process to launch idea64.exe and then exits immediately should avoid the failure, assuming Codex Desktop allows selecting such a wrapper as the editor opener.

Additional note

This machine has IDEA_VM_OPTIONS pointing to a custom VM options file containing:

-javaagent:C:\data\ckey_run\ja-netfilter.jar=jetbrains

Socket-level Java probes with and without this javaagent did not reproduce the failure, so this is not confirmed as the direct cause. It may still be a contributing factor because it changes JVM startup behavior and emits output during launch.

[xujiezhige]

这个方法可以解决（this url can solve thie problem)
#13937 (comment)