Troubleshoot Send Candidates API errors
Common Send Candidates API errors and how to resolve them.
How to detect errors
The Send Candidates API returns errors in two contexts:
- GraphQL responses: Most API errors return HTTP
200with error details in theerrorsarray - S3 upload responses: File attachment uploads return S3-specific error codes
Always check both the GraphQL errors array and S3 upload responses for failures.
Upload validation errors
S3 rejects file uploads that fail validation during the attachment upload step.
| Error code | Cause | Resolution |
|---|---|---|
SignatureDoesNotMatch | Missing or incorrect headers or content. | Verify that all headers match initialization values. |
BadDigest | File content does not match the MD5 checksum. | Verify file integrity and checksum calculation. |
AccessDenied | The pre-signed URL expired (URLs expire after 5 minutes). | Reinitialize the application to get a new URL. |