> [!CAUTION]
> **Caution:** This documentation is for Google Ads API **v23** . The latest active version is [**v26**](https://developers.google.com/google-ads/api/reference/rpc/latest/AdCustomizerErrorEnum.AdCustomizerError).

Enum describing possible ad customizer errors.

[Proto definition ![GitHub](https://developers.google.com/site-assets/logo-github.svg)](https://github.com/googleapis/googleapis/blob/master/google/ads/googleads/v23/errors/ad_customizer_error.proto)

| Enums ||
|---|---|
| ## `COUNTDOWN_DATE_IN_PAST` | Countdown end date is in the past. |
| ## `COUNTDOWN_INVALID_DATE_FORMAT` | Invalid date argument in countdown function. |
| ## `COUNTDOWN_INVALID_LOCALE` | Invalid locale string in countdown function. |
| ## `COUNTDOWN_INVALID_START_DAYS_BEFORE` | Days-before argument to countdown function is not positive. |
| ## `UNKNOWN` | The received error code is not known in this version. |
| ## `UNKNOWN_USER_LIST` | A user list referenced in an IF function does not exist. |
| ## `UNSPECIFIED` | Enum unspecified. |