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Codex app on Windows became extremely slow today even in /fast mode

OpenAI Developer Community March 9, 2026
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Hi team, I’d like to report a performance issue with the Codex app on Windows. Starting today, Codex has become extremely slow for me. A single response can take more than 20 minutes, even for a small project. My setup: * Codex app on Windows * Model: GPT-5.4 * /fast mode enabled * Repository size: around 20 files * Project is on a Windows path What makes this unusual is that the same setup was working much faster before. The slowdown started suddenly today. What I already checked: * Opened a brand new thread * Kept the task small * /fast mode is already enabled * The repo is very small, so this does not seem related to repo size * Previously, the same Windows-path workflow was fast, so this does not look like a simple “Windows path is slow” issue Observed behavior: * Codex stays in “thinking” for a very long time * Even simple prompts take 20+ minutes * The issue happens in new threads as well, not just old conversations Expected behavior: * Small tasks in a small repo should return much faster, especially in /fast mode Additional note: * I checked the public status page, and it appeared operational when I looked, so this may be a model-specific or app-specific performance issue rather than a broad outage Would the team be able to check whether there is any current latency issue affecting GPT-5.4 in the Codex app on Windows? Thanks.

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