USG20-vpn firwmare upgrade

Hi, I have a USG20 VPN that needs to be updated.
Current firmware is 4.30
The latest upgrade says "If the firewall running with previous version then ZLD5.00, we recommended upgrade to ZLD5.10 C0 or later version to Standby partition first before upgrading to ZLD5.31"

And the notes for firmware 5.30 (oldest available at the product page at says: "Recommended upgrade to ZLD5.10 Patch0 or later version first before upgrading to ZLD5.31"

Can I please have a links to all previous firmware version for the USG20 VPN ?
Thanks !


  • Zyxel_James
    Zyxel_James Posts: 610  Zyxel Employee
    First Anniversary 10 Comments Friend Collector First Answer
    I will provide 5.10 firmware to you via private message, please check your inbox.
    BTW, please know that we rename USG 20 VPN to USG FLEX 50 since V5.20, due to it can be deployed to on-premise and on-cloud mode.


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