20110524 16:48:30 :SMS_Send
20110524 16:48:30 :Object reference not set to an instance of an object.
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20110524 16:48:30 :SMS_Send
20110524 16:48:30 : at Inetlab.SMPP.SmppClient.VqEl9oC9Po6YdHt4Qla(Object )
at Inetlab.SMPP.SmppClient.Submit(SubmitSm ...

Dear Sir,
I have the below code for submitting SMS messages to the SMPP server, occasionally an exception is raised:
"object reference not set to an instance of an object"
can you please advise on what could be the problem and how to take care of it?

Thank you


List<Inetlab.SMPP.PDU.SubmitSm ...