Zoho Books API Error 41029 – Signed QR Code Rejected

Zoho Books API Error 41029 – Signed QR Code Rejected

Hello Team,

We are integrating our ERP with Zoho Books. Our ERP generates invoices and registers them with the Indian GST Invoice Registra​tion Portal (IRP). We then create the corresponding invoices in Zoho Books and manually associate the existing e-invoice details using the API.

The API works when we omit the signed_qr_code parameter. However, when we include the original SignedQRCode value received from the IRP, the API returns:

{
  "code": 41029,
  "message": "The digital signature could not be verified as this QR Code is not valid."
}



We are passing the original signed QR code without decoding or modifying it.
API endpoint:
POST /books/v3/invoices/{invoice_id}/einvoice/status/push
Could you please clarify:
  1. Does this API support signed QR codes generated externally by the IRP?
  2. What exact format is expected for the signed_qr_code parameter?
  3. Are there any additional requirements for validating an externally generated signed QR code?
  4. Is there a supported API workflow for associating an externally generated IRN and signed QR code with an existing Zoho Books invoice?
Please investigate this error and advise on the recommended integration approach.
Regards,
Thanks