ChatGPT Not Displaying Responses

Write-up

Summary

Between 10:46 PM PDT on September 2 and 2:25 AM PDT on September 3, some users accessing ChatGPT via the web interface experienced issues rendering responses, resulting in a blank UI. The problem lasted intermittently for about three hours and was resolved by 2:25 AM PT on September 3.

This incident was caused by misconfigured DDoS protection rules preventing certain JavaScript bundles from loading. The issue was resolved by resolving those misconfigured protections, and we have since improved detection and monitoring to prevent recurrence.

Impact

We estimate that up to 20% of page loads during the affected window failed to display responses. Many users found that refreshing the page resolved the issue, but for others responses were not displayed until the underlying cause was fixed.

Root Cause

The issue was traced to our content delivery network (CDN), where misconfigured automated security protections blocked delivery of certain static files required to display ChatGPT responses. Because those files could not load, the web client showed a blank response even though the assistant had generated one.

Resolution

Once identified, we resolved the misconfigured DDoS protection rules on our CDN. This quickly restored functionality for all users.

Prevention

To prevent similar issues in the future, we have:

Disabled automated blocking rules on domains that serve static assets.
Improved monitoring to detect missing frontend files more quickly to prevent recurrence.

We sincerely apologize for the disruption this caused. Ensuring reliable access to ChatGPT is a top priority, and we are committed to learning from this event to improve resilience and detection going forward.

Availability metrics are reported at an aggregate level across all tiers, models and error types. Individual customer availability may vary depending on their subscription tier as well as the specific model and API features in use.