Zoho Mail API - Upload Attachment

Zoho Mail API - Upload Attachment


I followed the steps from the API documentation and wrote a backend in JavaScript to send emails. Normal emails are sent without any problems. However, I can’t send emails with attachments.

As the documentation says, I first try to upload the file, but I get the following output:


  1. {"errorCode":"UPLOAD_RULE_NOT_CONFIGURED","status":{"code":404,"description":"Invalid Input"}}

I researched for hours and checked the documentation many times, but I can’t understand what the problem is. Why am I getting this error? Here is how I make the request:

  1. const formData = new FormData();
  2. formData.append("file", opts.file, opts.file.name || "attachment");

  4. const uploadRes = await fetch(`${baseUrl}/messages/attachments?uploadType=multipart`, {
  5. method: "POST",
  6. headers: {
  7.   Authorization: `Zoho-oauthtoken ${accessToken}`,
  8. },
  9. body: formData,
  10. });

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