Frequent dns_probe_finished_bad_config after connecting with FortiClient VPN
I'm having frequent dns_probe_finished_bad_config error (for every 5 to 10 min), after connected to FortiClient. At first thought it may issue with my router so checked with another (neighbour's) router and other 2 mobile networks faced same issue. Previously I have worked with Windows platform, there is no issue on those time. But recently I need to use Ubuntu (20.04.1 LTS), So installed in my new machine after that dns_probe_finished_bad_config started showing error for every small amount of time. Also verified with my mates those who are using FortiClient in Ubuntu, it's working fine for them. Any solution or lead will be helpful to me as I'm trying to troubleshoot this issue for nearly one month.
FortiClient version : 7.0.0.0018
Previously tried to solve this : Changed network, cleared dns cache, given manual and automatic DNS configuration
This problem seems typical for Forticlient on Ubuntu, CentOS, RedHat only. (shouldn't exists on Windows, Mac etc.)
The error "dns_probe_finished_bad_config" is observed in Forticlient 6.4.3+ and 7.0.0+ version. The issue is related to bad dns timeout settings and is planned to be fixed in FCT 7.0.4. If you have a paid-license version you can open a support ticket, where you can request a special build which has the fix already. If you use the free version you can try with release which is older than the above mentioned versions.