Https certificate problem during upload

Question

Hello,I have a https blazor site. I try use the FileUpload with Api endpoints but it always throws certificate exceptions in browser console:ERR_CERT_AUTHORITY_INVALID

Failed to load resource: net::ERR_SSL_KEY_USAGE_INCOMPATIBLE

We try with self-signed certificate, but not working.Can I disable the certificate check, or override it in Blazor similar as in Winforms?Thank you!BR, SZL

Mallesh Ravi Chandran · Answer

The errors you're encountering when using the Syncfusion Blazor SfUploader component are typically related to SSL certificate validation issues in the browser. Below is a brief explanation of the errors and their likely causes:

ERR_CERT_AUTHORITY_INVALID
This error indicates that the browser does not trust the self-signed certificate because it’s not issued by a recognized Certificate Authority (CA). Browsers expect certificates to be signed by trusted CAs (such as Let’s Encrypt or DigiCert) or to be manually imported and trusted on the client machine.

net::ERR_SSL_KEY_USAGE_INCOMPATIBLE
This suggests that the certificate’s key usage extensions (e.g., KeyUsage or ExtendedKeyUsage) do not align with the requirements for HTTPS. A valid certificate for HTTPS typically requires both digitalSignature and keyEncipherment usages. Self-signed certificates often lack these configurations, resulting in this browser-level error.

Syncfusion Blazor FileUpload

The SfUploader component sends HTTP requests to the specified SaveUrl and RemoveUrl (e.g., /api/SampleData/Save). If these endpoints are served over HTTPS with an invalid or misconfigured certificate, the browser will block the request, leading to the mentioned console errors.

Recommendations:

Use a properly configured self-signed certificate
Ensure the certificate includes the correct key usages. You can refer to this helpful Microsoft article:
How to fix the ERR_SSL_KEY_USAGE_INCOMPATIBLE error
Refer the issues ( Issues with self-signed certificates )
Understanding and fixing CERT_AUTHORITY_INVALID
Syncfusion FileUpload Configuration:
To ensure smooth operation, configure the SfUploader component to use a trusted HTTPS endpoint:

<UploaderAsyncSettings

SaveUrl="https://yourdomain.com/api/SampleData/Save"

RemoveUrl="https://yourdomain.com/api/SampleData/Remove">

</UploaderAsyncSettings>

</SfUploader>