Windows 10 VM under Proxmox unable to connect to a VPN

[scarlaxx]

Hello. I'm new to all this Proxmox, Linux, I learn this wonderful software as I go so my apologies if I miss something basic.
I've recently made a VM running a Windows 10 Pro 64bit. This virtual machine can access the internet, dns lookup works for the configured VPN hostname yet is is unable to connect to any VPN. Firewall is switched off in windows, no networking rule applies infrastructure-wise from Proxmox machine up to the internet.
I've already checked 3 VPNs on the same VM, none of them work. Tried with a different computer running the same Windows version and VPN configuration, all 3 of them work just fine.
HW settings screenshot for the VM is attached.
I was unable to google anything rly useful which either means I google with a wrong query or it is not a common issue.
Please advice whether I should search for the issue on the Proxmox side of things or in Windows.

Thank you!

 

[oguz]

hi,

yet is is unable to connect to any VPN

at which stage of connection does it fail? what error message do you get?

also what vpn client is in use?

you could also try changing the network interface type to e1000 or virtio

 

[scarlaxx]

Hello and thank you for your reply. I was in abroad so sry for my late reply.

at which stage of connection does it fail? what error message do you get?

It takes cca half a minute of trying and at the end it says: 'The network connection between you computer and the VPN server could not be established because the remote server is not responding. Ths could be ...' blah blah about firewalls, NAT etc. The same VPN settings work on another computer running the same windows version

you could also try changing the network interface type to e1000 or virtio

So far I tried switching to both, also tried to disable the firewall checkbox in proxmox NIC settings for VM. No effect on anything. Interestingly, I can ping the VPN server with any of the settings combination within around 15ms time.

also what vpn client is in use?

I'm not sure how to answer this. I'm using default built-in windows client with manual VPN settings.

Thank you

 

[oguz]

* what is the output of ipconfig /all from your windows VM?

* maybe also try running tracert your.vpn.ip.address

* is VPN using TCP or UDP connection?

 

[scarlaxx]

IpConfig and tracert outputs attached.
VPN is of type PPTP if that helps as I have no idea how to tell it uses TCP or UDP.

 

[oguz]

could you try opening a cmd prompt as Administrator and running:

REG ADD HKLM\SYSTEM\CurrentControlSet\Services\PolicyAgent /v AssumeUDPEncapsulationContextOnSendRule /t REG_DWORD /d 0x2 /f

was suggested here [0], it might work also in your case

[0]: https://answers.microsoft.com/en-us...ndows-10/5d3af73b-8c4a-414f-ac70-409358783377

 

[scarlaxx]

Thank you but this did not help either.

 

[scarlaxx]

Thank you again oguz but after I spend a couple of hours on this issue I installed a different VPN client provided by a company I work for. That client works with a different VPN settings so I will stick with that.