HTTP 203 Non-Authoritative Information vs 526 Invalid SSL Certificate
HTTP 203 (Non-Authoritative Information) is a 2xx Success response, while 526 (Invalid SSL Certificate) is a 5xx Server Error response. 203 indicates that the response payload has been modified by a transforming proxy from the origin server's 200 response. In contrast, 526 means that cloudflare-specific. The origin's SSL certificate could not be validated.
Description
The response payload has been modified by a transforming proxy from the origin server's 200 response.
When You See It
When a proxy or CDN modifies the response body (e.g., adds headers, transforms content).
How to Fix
Check if a proxy is modifying the response. Access the origin directly if you need the original content.
Description
Cloudflare-specific. The origin's SSL certificate could not be validated.
When You See It
When using Cloudflare Full (Strict) mode with an invalid origin certificate.
How to Fix
Install a valid SSL certificate on the origin, or use Cloudflare Origin CA certificate.
Key Differences
203 is a 2xx Success response, while 526 is a 5xx Server Error response.
HTTP 203: The response payload has been modified by a transforming proxy from the origin server's 200 response.
HTTP 526: Cloudflare-specific. The origin's SSL certificate could not be validated.
You encounter 203 when when a proxy or CDN modifies the response body (e.g., adds headers, transforms content).
You encounter 526 when when using Cloudflare Full (Strict) mode with an invalid origin certificate.
When to Use Which
For 203 (Non-Authoritative Information): Check if a proxy is modifying the response. Access the origin directly if you need the original content. For 526 (Invalid SSL Certificate): Install a valid SSL certificate on the origin, or use Cloudflare Origin CA certificate.