It sounds like a no-brainer, but quite often, the Airtames are put on their own VLAN with no internet access or they do not have access to port 80 for the Internet.
A temporary loss of WiFi can cause the download to stop and restart. If this happens once, it will likely keep happening.
We have found these firewall policies can block the download of new updates:
Make sure repos.airtame.com and http://airtame-firmware.b-cdn.net/ are accessible or whitelisted via your network/firewall. Keep in mind that whitelisting the IP address may not work long term as downloads could come from any global mirror.
You can also confirm any network connectivity by attempting to access the above links via a less restrictive network such as a public network or mobile hotspot.
There is a hidden settings page on Sonicwall firewalls you access by browsing to the hostname/diag.html. On this page, there is a setting called "Protect against TCP State Manipulation DoS". When this is enabled, Airtame updates fail. Disable "Protect against TCP State Manipulation DoS" and the update should now work.
Many network security software/hardware completely block any kind of compressed file from being downloaded. This includes .tar.gz files like Airtame's updates.
It can take up to 30-60 minutes to complete the update.
Your firewall may be blocking the installer since it comes as a .tar.gz file. This is seen on Sonic Firewalls.
If the update is stuck at the same percentage for more than 30 minutes, unplug the device and try again.
Updates happen over HTTP (TCP port 80) so ensure that this port is available on your network.
Be sure to use a power adapter instead of your display's USB port.
Try to put the device on a less restricted network, like a home network, to update.
Check your IDS/IPS systems for anything that can be preventing an update.