Getting Error: Image Upgrade Failed. Incorrect Address Name while trying to upgrade

[heyyo]

I am getting this error when trying to do Firewall upgrade:

"Image Upgrade Failed. Incorrect Address Name." while trying to upgrade

I am unable to find the KB which has the same problem.

How do I proceed with this?

Thanks!

[bkrishnan]

Hi 
Try to upgrade the device manually by following the upgrade path tool;
https://community.fortinet.com/t5/FortiGate/Technical-Tip-How-to-manually-perform-a-firmware-upgrade...
Upgrade path tool
https://docs.fortinet.com/upgrade-tool/fortigate