OpenAI Codex Hit by Widespread 401 Errors, Team Racing to Restore

On September 26, OpenAI Codex suffered a widespread service disruption, with a large number of user requests rejected and returning the 401 Unauthorized: Incorrect API key provided error — not an isolated case. Some users noticed that the sk-svcac-prefixed key appearing in the error message was never set by them, suggesting the problem lies on OpenAI's authentication side. As of when some users posted, OpenAI's status page had not yet flagged the incident.

Confirmed

Multiple users (including Reddit users, aidenybai, and Jeremy Philippe) reported that Codex was returning 401 invalid-key errors across the board, unrelated to their own keys.
OpenAI's official account later confirmed Codex is currently unavailable, apologized for the disruption, and said the team is working urgently on a fix.

Unconfirmed

The exact root cause (an authentication-side misconfiguration or something else) has no official explanation yet; the origin of the sk-svcac key is based on user-side observations and awaits clarification from OpenAI.

Why it matters

Codex is a key OpenAI coding tool for developers, and an authentication failure like this can disrupt the workflows of large numbers of users at once; the incident also exposed how the status page lagged behind the actual outage, which is worth noting for ops teams and dependents alike.

2026-09-26 ~ 2026-09-26 · 6 related posts

Primary sources

Codex hit by mass 401 'invalid API key' errors as OpenAI status page shows no outage — iamgarffi · 2026-09-26 06:48 (UTC+08:00)
Codex Desktop on Windows hits 401 "Incorrect API key" despite ChatGPT sign-in — Just_Another_User80 · 2026-09-26 07:33 (UTC+08:00)
Codex is down: OpenAI says it's hustling to restore service — prd_008 · 2026-09-26 07:24 (UTC+08:00)

Codex outage reports: users hit 401 'Incorrect API key' errors — aidenybai · 2026-09-26
[source] Codex hit by mass 401 'invalid API key' errors as OpenAI status page shows no outage — iamgarffi · 2026-09-26
OpenAI Codex outage: users hit "401 Incorrect API key" from OpenAI's own API — IgorCarron · 2026-09-26
[source] Codex is down: OpenAI says it's hustling to restore service — prd_008 · 2026-09-26
Codex outage: users hit widespread 401 Unauthorized errors — JeremyNguyenPhD · 2026-09-26
[source] Codex Desktop on Windows hits 401 "Incorrect API key" despite ChatGPT sign-in — Just_Another_User80 · 2026-09-26