Is it possible to use windows dco adapter in Windows Server ?

[ChauhanPriyanka]

Hi Team,
Could you please confirm whether the DCO adapter is supported on Windows Server 2019 or 2022?
I'm able to install it on windows server, however it does not show in the Network Adapter user interface in windows.
At present, I am using the TAP adapter on the server.
Kindly help.

[schwabe]

https://github.com/OpenVPN/ovpn-dco-win?tab=readme-ov-file#limitations

I think WIndows server 2019 is also supported but Windows Server 2022 definitively is.

Are you installing OpenVPN via the official installer or are you trying to install the dco driver yourself?

[lstipakov]

Sadly Windows Server 2019 appears to have an older kernel. We require at least 10.0.19041 (Windows 10 20H1), but Windows Server 2019 has 10.0.17763.

[ChauhanPriyanka]

Thank you for your response.
I am currently using the DCO driver from the following release:
https://github.com/OpenVPN/ovpn-dco-win/releases/download/1.3.3/ovpn-dco-win-1.3.3-amd64.zip

On Windows Server 2022 machine (build 10.0.20348.4052), the driver installs successfully, but the DCO adapter does not appear in the Network Adapters panel. This is the same behavior observed on Windows Server 2019.

In contrast, on a Windows 11 system (build 10.0.26100.6899), the adapter is displayed correctly in the Network Adapters UI.

[lstipakov]

Windows Server 2022 is indeed supported.

We don't know how do you install the driver. Could you try the official client installer? If it still doesn't appear, please provide the installer log msiexec.exe /i OpenVPN-2.7_alpha2-I002-amd64.msi /L*V log.txt. From there we should get some clues.

[ChauhanPriyanka]

Sure thank you, let me try.

[ChauhanPriyanka]

In Windows Server 2022, I installed the DCO driver using the OpenVPN installer, and in this case the driver did appear correctly in the Network Adapters list. However, when I try to install the standalone DCO driver manually (as shown below), it doesn’t show up in the Network Adapter UI. I’m not sure what I might be missing.

PS C:\CE\ovpn-dco-win-1.3.3-amd64\win11> pnputil /add-driver "ovpn-dco.inf" /install
Microsoft PnP Utility

Adding driver package:  ovpn-dco.inf
Driver package added successfully.
Published Name:         oem7.inf

Total driver packages:  1
Added driver packages:  1

[cron2]

not sure "install the driver" will also create an interface for you. You can use tapctl.exe to do that, from the OpenVPN package.

[ChauhanPriyanka]

I used devcon.exe to install the DCO driver, and the adapter appeared correctly in the Network Adapter UI. I also checked tapctl.exe, it shows, it is for tap/tun.

PS C:\openvpn-dco-installer> .\tapctl.exe help
OpenVPN 2.7_beta3
Usage:
tapctl <command> [<command specific options>]
Commands:
create     Create a new TUN/TAP adapter
list       List TUN/TAP adapters
delete     Delete specified network adapter
help       Display this text

[cron2]

tapctl create --hwid ovpn-dco

but indeed the help text needs work.