Regarding an error message "dco connect error: Access Denied.(errno=5)"

[Tetsu]

Hello all.

Good day.

When I tried to establish VPN connection,
I had an error message below.
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2023-02-10 18:28:04 MANAGEMENT: >STATE:1676021284,RESOLVE,,,,,,
2023-02-10 18:28:04 TCP/UDP: Preserving recently used remote address: [AF_INET] xx.xxx.xx.xxx:443
2023-02-10 18:28:04 ovpn-dco device [OpenVPN Data Channel Offload] opened
2023-02-10 18:28:04 dco connect error: Access Denied. (errno=5)
2023-02-10 18:28:04 Closing DCO interface
2023-02-10 18:28:04 SIGUSR1[soft,dco-connect-error] received, process restarting
2023-02-10 18:28:04 MANAGEMENT: >STATE:1676021284,RECONNECTING,dco-connect-error,,,,,
2023-02-10 18:28:04 Restart pause, 32 second(s)
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When I googled based on the error message, I could not find anyone who got the same one as I faced.

So let me post here for help to solve the issue.

Thank you.