GDMS > WP820 firmware fails with (Firmware signature error)


WP820 > upgrade to

Phone configures perfect from GDMS
Phone can reboot in about 30 seconds from GDMS
Push firmware to phone, 14 mins later phone says “Firmware signature error”.

Using Grandsteam Access points with 100Mb/s internet… !!


Dear user,

Thank you for using GDMS platform! This issue may be caused by the network issue in this upgrading case based on your error message. Could you kindly try to upgrade the WP820 again through GDMS platform? If you still encounter this issue, could you kindly help to capture the trace file and syslog for us so that we can help you troubleshoot this issue. Thanks for your testing!

Thank you!



I beleive we may have fixed this, it appears the device had not moved fully to GDMS, some actions (config / reboot) were working, but it still had some connections with the local UCM. After deleting the device (zero config) from the UCM and factory resetting, the firmware update appears to have taken.

We have other issues with the config from this point forward but will open a new thread if we need help with that.


Dear user,

Thanks for your update! We recommend users to only use GDMS platform and avoid the influence by other platform. After removing the device from local UCM Zero Config module, the device upgrading should work fine now. Thanks again for your testing. Let us know if you have any further questions.

Thank you!


Dear user,

Thanks for your testing! We checked the logs for this upgrading task in GDMS server side, and noticed that you upgraded 4 times, and the first 3 times failed, the last time attempt is successful. We thought this is a network issue, and the firmware file in GDMS platform has no problem. The firmware file is too large and this issue may generated during downloading process.

Thank you!


The issue was the firmware was not coming from GDMS, another location firmware location in the phone, the reason it was successful was the phone was factory reset, then the phone removed from the local UCM, thereby only getting config from GDMS, once this was done the firmware worked.

I have no idea how it can pull config from a UCM but still accept reboot commands from GDMS as it appears it allowed double management of the device.


Dear user,

Thank you for your feedback! The reason of the issue is the downloading firmware behavior of the device is not successful. The device can be managed by GDMS and UCM platforms at the same time, but if the user configures the device in both methods, it may cause conflict during managing the device. We suggest users to only use GDMS platform to manage the phone to avoid conflict. For example, if the user provisions the phone from GDMS and UCM, the phone will apply the changes based on the last time provisioning. If the user reboots the device through GDMS platform, and try to provision the device through UCM during this period, the provisioning operation will not be successful.

Thanks for your testing!

Thank you!