Keeps in state network registration denied

24 thoughts on “Keeps in state network registration denied

  1. Hi,

     

    We are running the modem over days but sometimes it
    gets into the state Network Registration Report == "registration
    denied" and keeps in that state over days. Only a restart of the whole
    modem helps to get a connection.

     

    You must know that the
    modem is running in a train and moves over the country. So searching for
    the next cell is normal. We set it to AT+COPS=0, AT#AUTOBND=0 and
    AT#BND=2,3. We can not restart always the whole pc because it depends on other systems.

     

    What would you recommend to reset searching for another carrier/cell again?

     

    Thank you for your response.

     

    Best regards

     

    Christoph

    1. Have you tried to set deregister AT+COPS=2 then re-register automatically AT+COPS=0? Or if this fails try manual registration finding operators with AT+COPS=? and then AT+COPS=1,<oper>.

      1. We tried to deregister and register, but it did not help. Even if there are networks around which are accessable. It did not help.

         

        Do you know another solution which could work?

         

         

        1.  Hi Christoph,

           

          is there any reason for choosing AT#BND=2,3 disabling the GSM 900MHz band ?

           

          This setting prevents to register to any 900MHz Operator in case WCDMA 2100 and DCS 1800 are not available.

           

          How do you check for available networks?

           

           

          1. is there any reason for choosing AT#BND=2,3 disabling the GSM 900MHz band ?

            I was wrong. It is AT#BND=0,3. I am setting always

             

            0 == Manual Mode 0 (900/1800 Europe) factory default and

            3 == always WCDMA 3 – 2100MHz(FDD I) + 1900MHz(FDD II) + 850MHz(FDD V) 

             

            If we power off the modem and startup from new it is working.

             

            Is there maybe a possiblity to reset the registration or other values without powering off?

             

            I tried already the following

             

            1. COPS=2, wait 10 seconds and set then COPS=0

            2. an AT#REBOOT command

             

            Do you have another idea?

             

            Maybe it helps to know that we are running the modem in Czech and with O2 sim card.

             

             

             

          2. Hi Andrea,

             

            We do not use AT#BND=2,3 . I was wrong we set 0,3 so the normal GSM 900 and 1800.

             

            I tried until now

            – COPS=2, wait 10 seconds, COPS=0

            – AT#REBOOT

             

            both did not help.

             

            Do you have maybe another solution to reset the registration state?

             

            Thank you for your support.

          3. Some enhancement on module registration and network handling was introduced from 8.01.106 to 8.01.108 but I cannot say if they fit to your requirements.

             

            A special trace would be needed to analyse in deep the issue you are facing.

            In any case I would suggest to test at least one module with the latest 8.01.108 to verify the behavior in that specific condition.

          4. Hi Andrea,

             

            Could you please send me the changelog for 108 or Delta SW version 8.01.x07 – 8.01.x08.

             

            Thank you.

             

            Br

             

            Christoph

      2. Have you tried to set deregister AT+COPS=2 then re-register automatically AT+COPS=0? Or if this fails try manual registration finding operators with AT+COPS=? and then AT+COPS=1,<oper>.

        Hello, any ideas what this could be? We have talked to our operator (Telenor) and they can see in their logs that they give our modem ok. Shortly after it deregisters and tries again. This is as expected since our procedure is:

        1) Register

        2) Check results. If denied, deregister and go to 1

        3) Online!

        The operator gives the modem ok but the modem says to us that it got denied.

        1. when the module is not registered and in denied state, what is the response of AT#CEERNET and AT#CEER  ?

          Module used and firmware version?

          Is it systematic at power on?

          1. when the module is not registered and in denied state, what is the response of AT#CEERNET and AT#CEER  ?

            Module used and firmware version?

            Is it systematic at power on?

            I’ll add a hook for those commands so we can see it the next time it happens. It’s not systematic. On my dev systems I usually get it maybe once per day. In production it’s less frequent, maybe once a week, but it’s as bad since there’s no way of getting out of it (that we know of) other than a physical reset.

            Edit: Module is UL865, firmware is 12.00.614.

          2. when the module is not registered and in denied state, what is the response of AT#CEERNET and AT#CEER  ?

            Module used and firmware version?

            Is it systematic at power on?

            Ok, now I managed to capture the error codes:

            AT#CEERNET  ->  #CEERNET: 3

            AT#CEER  ->  #CEER: 225

          3. It seems NWT requested the detach for illegal MS.

            This cause is sent to the MS when the network refuses service to the MS either because an identity of the MS is not acceptable to the network or because the MS does not pass the authentication check, i.e. the SRES received from the MS is different from that generated by the network. When used by an MM procedure, except the authentication procedure, this cause does not affect operation of the GPRS service.

            Can you please describe your power off/reset procedure? Do you turn off the module via ON/OFF line?

          4. It seems NWT requested the detach for illegal MS.

            This cause is sent to the MS when the network refuses service to the MS either because an identity of the MS is not acceptable to the network or because the MS does not pass the authentication check, i.e. the SRES received from the MS is different from that generated by the network. When used by an MM procedure, except the authentication procedure, this cause does not affect operation of the GPRS service.

            Can you please describe your power off/reset procedure? Do you turn off the module via ON/OFF line?

            We originally saw this in the first implementation where we just cut the power to the modem. We figured the operator threw us out for not deregistering, so we implemented a graceful shutdown:

            1) Deactivate GPRS: AT#SGACT=1,0

            2) Deregister from oper: AT+COPS=2

            3) Exit Python interpreter: raise SystemExit

            4) Cut Modem power line

            Our operator have checked their logs and cannot find any problems or anything deviating. They can see that the modem sends a deregister request after the modem has registered and the services have been activated. This is expected since we deregister in software after getting denied.

            It’s also worth mentioning that we do not always have to power the device off to get this problem. When the MCU starts up it assumes that the modem is in AT mode, so it starts initializing it. When the Python application detects this it runs #1, #2 and #3 (that is, deactivate GPRS, deregister and exit) so the MCU can do its regular initialization before jumping back into Python. In this case the modem is never turned off, yet the problem appears from time to time.

          5. Hi,

            is there any reason to cut off the power instead of using the ON_OFF pad has per HW User Guide? Do you have the line always grounded for auto power on?

            Anyway some recommendations:

            – AT+COPS=2 deregisters from GSM but not from GPRS. You can add AT+CGATT=0 to detach GPRS service, but it can be simplier to use the command AT+CFUN=4 to deactivate the SIM (this action deregisters completely the module). Check with AT+CREG? and AT+CGATT? that both are 0, before cutting the power.

            – In case you are terminating python without shutting down the module, do you really need to deregister it? Why not keeping the module registered to the network? Also in this case if you really have to do this operation, please use AT+CFUN=4.

            AT+CFUN=1 to restart in operative mode.

    2. Hi,

       

      We are running the modem over days but sometimes it gets into the state Network Registration Report == “registration denied” and keeps in that state over days. Only a restart of the whole modem helps to get a connection.

       

      You must know that the modem is running in a train and moves over the country. So searching for the next cell is normal. We set it to AT+COPS=0, AT#AUTOBND=0 and AT#BND=2,3. We can not restart always the whole pc because it depends on other systems.

       

      What would you recommend to reset searching for another carrier/cell again?

       

      Thank you for your response.

       

      Best regards

       

      Christoph

      Did you ever solve this? We are having the same issue with both development devices (which are rebooted regularly) and a system which wakes up every hour tro transmit data. After a few days the device is stuck in denied mode. Every time the device is shut down we issue a COPS=2 to deregister from the network.

  2. Hello Cosmin,

     

    I  follow your suggestion and re-register with COPS=2.

    I can’t understand why we have still a GPRS touch after re-register?

    AT+CGMR

    10.00.055

    AT+CREG?

    +CREG: 0,1

    AT+CGATT?

    +CGATT: 1

    AT+cops=2

    OK

    AT+CREG?

    +CREG: 0,0

    AT+CGATT?

    +CGATT: 1

     

    Your hint is highly appreciated.

    Thanks

     

      1. AT+CGMR

        10.00.055

         

        AT+CGREG?

        +CGREG: 0,1

         

        AT+CGATT?

        +CGATT: 1

         

        AT+COPS=2

        OK

         

        AT+CGATT?

        +CGATT: 1

         

        AT+CREG?

        +CREG: 0,0

         

        AT+CGREG?

        +CGREG: 0,1

         

         

        1. Hi,

          this is because at+cops=2  deregister from the network, but for the GSM part only. You need to use at+cgatt=0 if you want to deregister also from the GPRS "word"