Codex Desktop can spike Windows 10 CPU to 100% with Defender and WMI on launch
ramisasa9080-blip · ghdev · 2026-07-18
What happened
A Windows 10 user reports that launching Codex Desktop immediately drives CPU usage to 90–100%, even before opening any project.
Reported cause
- ChatGPT / Codex processes are part of the load.
- Windows Defender (Antimalware Service Executable) takes 20–40% CPU.
- WmiPrvSE.exe also rises to 10–20% CPU.
- The machine gets noticeably hotter while Codex sits on the home screen.
Troubleshooting already tried
- Added Defender exclusions for the project folder, AppData\Local\OpenAI, and Codex runtime paths.
- Disabled Defender real-time protection.
- Rebooted Windows.
- Checked WMI logs and rebuilt performance counters.
- Verified the CPU behaves normally outside Codex.
Notable observation
When Defender real-time protection is disabled, Defender CPU usage disappears, but Codex CPU usage rises instead, suggesting an interaction between Codex Desktop and Windows security/monitoring components.
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