SSL/TLS validation failed in COPY activity

Hi KNULLByTE,

The error occurs because Microsoft Fabric enforces strict SSL/TLS certificate validation when connecting to HTTPS endpoints. If the REST API you are calling uses an invalid certificate—such as a self-signed, expired, or domain-mismatched certificate—Fabric will reject the connection with a "TrustFailure" error. This validation happens even if you're using an on-premises data gateway or have set the privacy level to None, as these settings do not bypass SSL security checks.

To resolve this, you need to ensure the API uses a valid SSL certificate issued by a trusted certificate authority. If updating the certificate is not possible, a common workaround is to set up a reverse proxy (e.g., NGINX or Azure API Management) with a trusted SSL certificate that forwards requests to the original API. This allows Fabric to successfully establish a secure connection through the proxy, while the proxy handles communication with the original API.

let me know if your still blocked on this?

Thanks,

Prashanth Are

MS Fabric community support

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly and give Kudos if helped you resolve your query