GXV3370 Firmware Upgrade issue



I have a lot of gxv3370 on different sites.
I always use the same method to upgrade the phones.
I use my own server to host the file.
On a specific site i am getting this error:
Failed to detect firmware version, please check your firmware server path


The HTTP server path is working well and i can download the firmware from a browser without problem.
I am wondering on this specific site why it’s not working.
The server is on the same LAN as the phones.
The LAN has no internet access, can it be related?

One thing i noted is that the servers on this site starts by 172.xx.xx.xx instead of the classic 10.xx.xx.xx or 192.xx.xx.xx.

Anyone knows this issue?

Phones have different firmware versions so it’s not firmware dependant,,

It seems like the phone is not even trying to download the file at all.

thank you!


All of the IP ranges you mentioned are all acceptable, common private IP ranges -

Not knowing how the firmware server on the phone is set along with how it timed to check makes providing any guidance problematic.


I am using the Update Detect button to check for update right now.
Here is a picture of the current setup