plz help me out in updating the version in my x-ctu software

am using xb24 accepts only 1084 version.i tried of updating the version 10c8. i enabled the always update firmware check box and i followed all the steps correctly as said by the digi techs even though i can’t update it. it shows that lost modem write parameter is failed. even in 1084 version if i enabled always update firmware then my write is failed .only when i disabled the always update firmware option then only my write is success in 1084 version. in other versions whatever i do my write is failed. i can’t use my modem up pate from 1084.

I just updated my series 1 firmware to 10A5 without any problems. When I tried 10CD (10C8 not shown in my X-CTU), it showed the same message as described by you.
I faced similar problem in series 2 modules where some firmwares dont load. Is it because hardware and firmware versions have to match???