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Captcha:Client initialization errors

Last Updated:Nov 13, 2025

Initialization API error codes

The Captcha initialization API requests Captcha resources. The request includes a user tag and is sent to the domain name xxxxx.captcha-open.aliyuncs.com. In this domain name, `xxxxx` represents the user tag. For more information about how to obtain a user tag, see Activate Captcha Service. The following figure shows the response for a successful initialization request:

image.png

If the initialization API request fails, the following table describes the failure responses and provides troubleshooting suggestions:

Error code

Description and troubleshooting suggestions

IllegalUserTag

The user tag (prefix) parameter is invalid. See Activate Captcha Service to confirm that the parameter is passed correctly.

Important

IllegalUserTag applies only to Web and H5 client integration and App client integration. It does not apply to WeChat mini program integration.

IllegalCertifyId

The format of the custom `certifyId` (UserCertifyId) parameter is invalid. Confirm that the parameter format is: User tag (prefix)_10-digit random string that contains uppercase letters, lowercase letters, and digits. For code samples, see UserCertifyId parameter code samples.

IllegalScene

The scene ID (SceneId) parameter is invalid. Confirm that the passed SceneId parameter is correct. Make sure that the scene ID is created under the account that is associated with the user tag (prefix).

Forbidden.AccountAccessDenied

The user account has an overdue payment. Confirm that the account status is Normal.

Throttling

API rate limiting is triggered. The number of queries per second (QPS) exceeds the product limit. If you require a higher QPS, contact your account manager in advance for confirmation.

ThrottlingByStrategy

Initialization request rate limiting is triggered. This blocks attackers who frequently send requests to traverse the Captcha question library.

Field

Error description

General type verification

The type of the passed parameter is invalid. See Parameter description and pass a value of the corresponding type.

language

The value passed for the language parameter is invalid. See Languages supported by Captcha 2.0.

region

The value passed for the region parameter is invalid. See region parameter description to check if this parameter meets the requirements.

mode

The value passed for the mode parameter is invalid. The supported values are popup and embed. See mode parameter description to check if this parameter meets the requirements.

element/button

The value passed for the element/button parameter is invalid. Make sure that the element/button element exists on the page and that the element/button parameter matches the ID selector of the element/button element on the page.