Dear all, I also send SMS over a german SMS service-center from t-mobile. I allways send OT51 with request for notification. The Notificatin is received from a extra Script with wait_in_loop. Generelly this works good, and i can assign the notification to the send SMS with the Field sm in the receifed OT51-result. But sometimes I receive a OT-53 in the error-text instead of the expected OT51-result. In that case, I get no Id of the send message, and I can't assign the later received notification to the send sms (and so to the email of the sender). Is there a way to avoid this? Or is there another way to assign the notification to the sender? Thanks for any help, kind regards, Klaus Schuetz