data channel offload doesn't support data_v1 packets. upgrade your server to 2.4.5 or newer. - SERP Analysis

https://github.com/OpenVPN/openvpn/issues/422

https://patchwork.openvpn.net/comment/6262/

https://www.reddit.com/r/PrivateInternetAccess/comments/j1iyl7/openvpn_client_no_longer_connects_cipher_not/

https://www.vpnusers.com/viewtopic.php?t=68316

https://patchwork.openvpn.net/comment/6255/

https://forum.opnsense.org/index.php?topic=46290.0

https://sourceforge.net/p/openvpn/mailman/message/47740451/

https://forum.netgate.com/topic/173235/openvpn-data-channel-offload-dco-failure-service-does-not-start-after-upgrade-to-version-22-05-release-amd64

https://forum.opnsense.org/index.php?action=profile%3Barea=showposts%3Bu=24834

https://marc.info/?l=openvpn-devel&m=169797160314105&w=2

https://github.com/OpenVPN/openvpn/blob/master/src/openvpn/forward.c

https://www.mail-archive.com/openvpn-devel%40lists.sourceforge.net/msg27214.html

https://hardforum.com/threads/openvpn-is-still-alive-and-kicking-with-new-wintun-and-data-channel-offload-adapters.2034763/

https://www.youtube.com/watch?v=XioSr3CVuGo

https://www.mail-archive.com/openvpn-devel%40lists.sourceforge.net/msg27146.html

https://superuser.com/questions/1714036/upgrading-openvpn-2-4-7-to-2-5-6-results-in-frequent-disconnects

https://docs.netgate.com/pfsense/en/latest/vpn/openvpn/dco.html

https://vpnki.ru/questions/support-forum/tuns-routing/1057-utilita-openvpn-gui-dlya-windows10-oshibka-avtorizatsii

https://forum.hackthebox.com/t/openvpn-negotiated-cipher-not-allowed/259904

https://www.2cpu.co.kr/network/16332?&page=3220

https://www.reddit.com/r/OpenVPN/comments/15gzqcx/going_insane_over_trying_to_fix_a_tuntap_error/?tl=ru

https://ntc.party/t/%D0%BE%D0%B1%D1%85%D0%BE%D0%B4-%D0%B1%D0%BB%D0%BE%D0%BA%D0%B8%D1%80%D0%BE%D0%B2%D0%BE%D0%BA-%D0%B2-%D1%80%D0%BE%D1%81%D1%81%D0%B8%D0%B8-%D1%87%D0%B5%D1%80%D0%B5%D0%B7-%D0%B0%D0%BD%D1%82%D0%B8%D0%B7%D0%B0%D0%BF%D1%80%D0%B5%D1%82-%D0%BD%D0%B0-%D0%BF%D1%80%D0%BE%D1%88%D0%B8%D0%B2%D0%BA%D0%B5-keenetic/7768?page=7

https://developer.aliyun.com/ask/636423

https://www.2cpu.co.kr/network/16332

https://forum.dd-wrt.com/phpBB2/viewtopic.php?t=335408&sid=68921000b6701eb541f6ae71f7895ccc

https://airvpn.org/forums/topic/53820-openvpn-dco-data-channel-offload/