Internet connection is lost at random times when Windows VPN is active

Question

I am a seasoned Windows user and software developer (30+ years). I have done a lot of testing to try to figure out this problem but I am at a loss.

I'm running Windows 10 on two different computers and the same problem occurs on both of them. I work from home and the firm I work for has an internal network that hosts various resources (servers and software). They have a dedicated Windows Server acting as a VPN server for users who need remote access, like me. I launch a Windows VPN client connection on my Windows 10 systems to gain access to the internal network. BUT fairly recently the VPN client connection has become very unreliable with regard to maintaining an internet connection. Usually, my internet connection is fine for a period of time after I launch the VPN. However, after an indeterminate amount of time (anywhere from seconds to a few minutes to sometimes a few hours) I lose internet connectivity. The Windows VPN network status property window claims the VPN is connected and internet is available. But any application I run that requires an internet connection fails at this point. I must stop the VPN client in order to regain internet. Restarting the VPN simply repeats the cycle.

My home network environment is wired TCP/IP through a TP-Link Deco router. My ISP provides fiber network service (fiber modem) with at least 1 Gbps speed. Network service is fine if I am not using the VPN.

The internet drop-out problems started to occur after I switched from my previous ISP and an older DSL network service (and a different network router). VPN connections to my work network were reliable under this old system (but the underlying DSL network was unreliable and would drop out frequently, which is why I switched).

I have run the Windows networking troubleshooter, both before and after the VPN has lost internet. When internet is working, the troubleshooter finds no problems (as one would expect). After internet is lost, the troubleshooter reports that no DNS server can be located.

I have involved my work network administrator to try to diagnose the problem. He says the VPN server can identify when I connect but it does not show any obvious errors when internet is lost.

I have checked the Windows event log on my home computers. No errors related to networking are reported.

I am out of ideas and the experienced support tech at my work is as well. It appears that Windows does not (obviously) provide the diagnostics we need to resolve the problem. I am open to suggestions from the community.

Jeff

***moved from Windows / Windows 10 / Internet and connectivity***

Answer 1

I had another internet drop out. This time I discovered an event log error (System logs). I somehow had never looked in the System logs before now. This error may only be a symptom but maybe it's a clue:

"The system failed to register host (A or AAAA) resource records (RRs) for network adapter

with settings:

           Adapter Name : {...}

           Host Name : <computer name>

           Primary Domain Suffix : <work domain name from VPN connection>

           DNS server list :

              <DNS IP 1>, <DNS IP 2>

           Sent update to server : <?>

           IP Address(es) :

             192.168. ...

The reason the system could not register these RRs was because the update request it sent to the DNS server timed out. The most likely cause of this is that the DNS server authoritative for the name it was attempting to register or update is not running at this time.

You can manually retry DNS registration of the network adapter and its settings by typing 'ipconfig /registerdns' at the command prompt. If problems still persist, contact your DNS server or network systems administrator."

Event Source: DNS Client Events

Event ID: 8015

What is peculiar about the above is that <DNS IP 1> & <DNS IP 2> are for the DNS servers assigned by my home router & ISP. They are different than the DNS servers (presumably active) assigned from my work/VPN (one of those is the public DNS IP, 8.8.8.8).

I can't really interpret what this error is telling me. I can say that under normal conditions, I can ping both DNS IP 1 and 2 successfully. I haven't yet tried to use 'ipconfig' to restore DNS settings after a drop out.

Thoughts?

Answer 2

Hello Jeff,

It is either a symptom of or unrelated to the connectivity problem.

Gary

Answer 3

I'm just going to mention that I have the same problem.

I'm using Windows VPN and L2TP.

It seems to randomly mess up my normal internet connection.

When it does, the wifi connection in the taskbar shows VPN when it pops up.

The VPN is not connected and not set for automatically connecting.

The problem goes away if I remove the VPN (there doesn't seem to be any way to just disable the VPN instead of removing it).

Answer 4

I have something for you to check.

When this happens, click the start menu and type in inetcpl.cpl.

On the connections tab, click LAN settings.

I found "use a proxy server" was checked and I don't use a proxy server.

Not sure how or when it got checked and I just removed the VPN, so I can't troubleshoot.

Answer 5

I checked the connections settings for the VPN. Proxy server was not checked at any time (that is, before starting the VPN, after VPN internet connection dropped out, etc.).