Windows 10: Npcap Loopback Adapter (Dec 2017 Win 10 Update) interfering with VPN?

  1.    4 Weeks Ago #1

    Npcap Loopback Adapter (Dec 2017 Win 10 Update) interfering with VPN?


    Hi,

    Over the last few weeks I have been having endless problems in using my VPN (PIA) via its Win 10 App. The VPN has been informed of the problem.

    I have also noticed that a recent Win 10 Update installed something called Npcap Loopback Adapter. After searching on the Net I can find nothing positive or useful about the Npcap Loopback Adapter. Seems like something designed for Microsoft's benefit that provided nothing for its average user.

    So has anybody else had problems with this thing and more importantly is it safe to Disable and or even Un-install.

    It does not appear to provide any benefits to me.

    Looking forward to some assistance and solving this annoyance.
      My ComputerSystem Spec

  2.    4 Weeks Ago #2

    Npcap doesn't come from default Windows, it's a promiscuous capture driver "shim" (something that gets inserted into the normal Windows IP stack) for programs like Wireshark to grab IP packets from your network interface so they can be analyzed and displayed. While it may be causing problems, it's not part of Windows per se. As an experiment you could either disable it or uninstall it, and see if that fixes your problems.
    HTH,
    --Ed--
      My ComputersSystem Spec

  3.    4 Weeks Ago #3

    EdTittel said: View Post
    Npcap doesn't come from default Windows, it's a promiscuous capture driver "shim" (something that gets inserted into the normal Windows IP stack) for programs like Wireshark to grab IP packets from your network interface so they can be analyzed and displayed. While it may be causing problems, it's not part of Windows per se. As an experiment you could either disable it or uninstall it, and see if that fixes your problems. HTH,
    --Ed--
    Thanks for getting back Ed.

    I have no idea where the Npcap Adapter came from as I do not use Wireshark. While I do use Glasswire as a GUI for Windows Wirewall but the guys at Glasswire say that the Npcal Adapter has nothing to do with Glasswire.

    I have disabled the Npcap Adapter but that does not seem to solve the PIA Windows App problem. Perhaps I should uninstall it to make sure there is no potential interference?

    My next candidate may be the TAP-Windows Adpater V9 and I have taken that up with my VPN PIA.

    Weirdly while the PIA Windows App does not seem to work anymore after the start of 2018 their Browser App for Chrome based Browsers works perfectly.

    I have also updated both Glasswire and PIA to their latest versions.

    Checked for any Windows Updates but nothing there.

    Onward, forever onward.

    laopa
      My ComputerSystem Spec

  4.    4 Weeks Ago #4

    Npcap (or as I usually call it WinPCap) provides wire-level IP access to all kinds of applications, so who knows how it got there. Try uninstalling it and see if any of your apps quit working as a consequence. It may help fix your problem. Q: is "PIA" a real app name, or is it just short for Pain-In-the-A<youknowtherest>? Just curious!
    If you're not using Npcap, hopefully there'll be no adverse fall-out from taking it out of the picture. Please let us know how this turns out.
    Thanks,
    --Ed--
      My ComputersSystem Spec

  5.    4 Weeks Ago #5

    Sorry, PIA is Private Internet Access and is the VPN I use. Mind you the Windows App version is currently being a Pain.

    My pennies worth is that something else is causing the problem. Glasswire says it isn't them and npcap has been nobbled but still no go with the PIA Wondows App.

    Luckily as I have mentioned the PIA (Private Internet Access) Browser Apps for Chrome based Browsers works.

    I'm also still pushing the TAP-Windows Adapter V9 issue as the culprit and hopefully can cross that one off shortly.

    I'll get to uninstalling npcap today and will get back with the results.

    laopa
      My ComputerSystem Spec

  6.    4 Weeks Ago #6

    Thanks for following up with this reply, and future replies. I learn the most when I get to see all the steps between problem and resolution. Have a great weekend.
    --Ed--
      My ComputersSystem Spec

  7.    4 Weeks Ago #7

    EdTittel said: View Post
    Thanks for following up with this reply, and future replies. I learn the most when I get to see all the steps between problem and resolution. Have a great weekend.
    --Ed--
    Well what do you know.


    Based on discussions and the support from Glasswire I reinstalled Glasswire again with the “clean install” and “reset firewall to default” options checked and voila every thing with my PIA (Private Internet Access) VPN Windows App is fixed.


    So, not the VPN's fault but I still suspect that Microsoft was in the background somewhere. Why else did I need to set the Windows Firewall back to its default settings which had worked fine with everything, VPN Windows App and Glasswire until January this year of 2018.


    Thanks to the folks of this TenForums and particularly Ed, for their assistance and great support.


    My VPN Private Internet Access also did a great job with their support in trying to help me figure this out.

    I might ponder on the uninstalling of the npcap adapter a might longer, although it appears not to have been, at least the cause of my problem, whether it provides any benefits is still unknown, as is its origin

    In terms of my pursuit of the TAP-Windows Adapter V9 issue as being involved I might hold back on further efforts in that direction as well


    laopa
      My ComputerSystem Spec

  8.    4 Weeks Ago #8

    Dear Iaopa:
    Glad you got it sorted. There are so many interactions in a "normal" Windows install that you will often find yourself wondering how you fixed a problem, even after it's been put to bed. But still, things are working now, so revel in it!
    --Ed--
      My ComputersSystem Spec

  9.    4 Weeks Ago #9

    EdTittel said: View Post
    Dear Iaopa:
    Glad you got it sorted. There are so many interactions in a "normal" Windows install that you will often find yourself wondering how you fixed a problem, even after it's been put to bed. But still, things are working now, so revel in it!
    --Ed--
    You wouldn't believe it but the exact same thing just happened to my kid's (attending University) Win 10 HP Laptop.

    Completed a Windows Update (they are not very proactive with updates, scans, maintenance etc.) and the VPN PIA Windows App no longer worked. Exact same Windows Firewall blocking issue.

    Luckily, after spending near on 2 weeks with my desktop and the exact same problem we were able to sort it out in short time.

    We can't be the only ones out here facing this problem?

    laopa
      My ComputerSystem Spec

  10.    3 Weeks Ago #10

    Probably not. If your theory is correct, we'll start seeing "I signed up for this forum just to thank you for this fix" messages. Let the games begin! ;-)
    --Ed--
      My ComputersSystem Spec


 

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