DB65 is a SMS 365, enterprise service status code, which indicates that the Operator/SMSC was unable to deliver the MT message within the Validity Period (VP), defined for the message.
The Validity Period can be set to a period of seconds, minutes, hours, days or weeks in varying increments up to one year, and is set for each MT message.
Possible reasons why a MT message may expire
There are a number of reasons why the operator SMSC was unable to deliver the MT message within the validity period set, some of which are detailed below:
Category
Description
Action
Handset
The handset is not on the network and so is unreachable. In such cases the operator network in general has not received the ‘handset switched off’ signal and therefore is ‘absent’ from the operator network
The end-user should ensure that the handset is switched on and correctly connected to their network operator.
Faulty handset and reception issues should be addressed by the end-user with their network operator.
Handset
The handset is switched off and a signal from the handset to the operator confirms this action. In this case, the message will be set to retry until the validity period has expired
The end-user should ensure that the handset is switched on and correctly connected to their network operator.
Handset
The handset is in a low coverage area causing intermittent connectivity to the operator network resulting in messages to the handset to not be correctly delivered
This can also cause handset acknowledgement issues, whereby the notification can either, not be sent or is sent but arrives with delay, by which time the message is entered into, or remains in the retry cycle until the message expires
The end-user should ensure that the handset is correctly connected to their network operator.
Faulty handset and reception issues should be addressed by the end-user with their network operator.
Handset
SMS inbox is full.
The end-user should delete any unwanted SMS messages from the inbox to allow new SMS messages to be correctly delivered.
End User
The end user (and by extension the handset) is roaming on another network
In general a MT message sent to a MSISDN which is roaming is ‘best effort’, and is not guaranteed, however where peering agreements exist, the possibility of message delivery increases, although these messages are subject to many more constraints and delays which may result in message expiry
The end-user should use a local operator with whom their home network operator has a peering agreement.
This increases the possibility of message delivery, however any such message, is subject to many more constraints and delays, which may still result in message expiry
End User
The end user has a pre-pay account, where there is no credit remaining on the account sufficient to keep the end user on the network; This will put the MT into a retry cycle.
The end-user should ensure that there is sufficient credit remaining on the account to send and receive SMS messages and to keep the handset connected to the operator network.
... View more