WP Mail SMTP 플러그인 오류내용입니다.

Heads up! The last email your site attempted to send was unsuccessful.

Email Source: WP Core
Mailer: Google / Gmail
{
"error": {
"code": 401,
"message": "Request is missing required authentication credential. Expected OAuth 2 access token, login cookie or other valid authentication credential. See https://developers.google.com/identity/sign-in/web/devconsole-project.",
"errors": [
{
"message": "Login Required.",
"domain": "global",
"reason": "required",
"location": "Authorization",
"locationType": "header"
}
],
"status": "UNAUTHENTICATED",
"details": [
{
"@type": "type.googleapis.com/google.rpc.ErrorInfo",
"reason": "CREDENTIALS_MISSING",
"domain": "googleapis.com",
"metadata": {
"service": "gmail.googleapis.com",
"method": "caribou.api.proto.MailboxService.SendMessage"
}
}
]
}
}

For more details please try running an Email Test or reading the latest error event.
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