Hello,
For MAKRKETINGCLOUD.  I am trying to update a Data Extension for a triggered send via Rest API and I get the following error message "Invalid request, this operation has not been enabled for this Account or Data Extension"
This is the call and the error message:
https://www.exacttargetapis.com/data/v1/async/dataextensions/key:external_key/rows
{
    "requestId": "9bb96b47-7043-465f-8fcd-024979dd06f9",
    "resultMessages": [
        {
            "resultType": "Validation",
            "resultClass": "Error",
            "resultCode": "OperationNotAllowed",
            "message": "Invalid request, this operation has not been enabled for this Account or Data Extension."
        }
    ]
}
On the installation package I had turned on all the options, including READ/WRITE on dataextensions and the user I log in as has the appi user option switched on
Is it possible to update a Data Extension via REST API or should I use SOAP? in case it is possible, what am I doing wrong?