Need More Info
Last Updated: 25 May 2021 08:16 by ADMIN
Created on: 14 May 2021 13:28
Type: Feature Request
Fiddler Everywhere with windows 10 build in VPN Settings



I am trying to use Fiddler Everywhere for capturing my localhost aspnet core 3.1 mvc application. I am able to use it when not using VPN.

But there are some scenarios for which I need to debug with my VPN connection ON, but fiddler does not shows any traffic after I have connected to VPN.


I am using windows 10 built in VPN.


And also configured it in Bypass Fiddler section of Fiddler Everywhere as recommended in some KB blogs.


I feel that my bypass Fiddler string is not correct. However. I  have tried various combination and it does not works with any of the string

Tried all these but nothing worked.,


I tried to do 

ipconfig /all

but was not sure which section to check..  I am adding the info that I see related to the section with the name of my VPN,


the IP is pinging , but does not shows up.

Nick Iliev
Posted on: 25 May 2021 08:16

Hi Rahul,


Indeed, Fiddler Everywhere is not officially supporting all the VPN types provided as an option in the built-in Windows 10 VPN manager. The team is currently investigating the possibilities and will plan accordingly. The issue is now marked as a feature request and I will post any related information in this thread.

Meanwhile, if possible, could you please provide more information about your case as follows:

- Provide the Fiddler Everywhere log files to investigate more about the application failure when using the specific VPN type.

- Share more about your VPN setup. The screenshot indicates that you/your company is using L2TP/IPSec with a pre-shared key - is that a correct assumption? Could you please clarify more if the VPN allows accessing localhost addresses (when no Fiddler proxy is turned on)? Is there any other specific to the network setup?


Nick Iliev
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Posted on: 20 May 2021 18:40



I have already added the snapshot from the document that you referred in my previous mail.

And just to answer you, its not that I have not only looked through the document, I have also invested couple of hours trying to make it correct.

But I just couldn't. Is Fiddler Everywhere software only compatible with AnyConnect?

How did you all not cared to put a document on connecting with windows default VPN settings on Fiddler.

I also double verified to check if my public IP after connecting to VPN was correctly mentioned in Fiddler Anywhere settings, and is it not same to the address of VPN .


But it is same.

 Adding one more snapshot..


Please help me with clear answer to this simple question , if you could?

Nick Iliev
Posted on: 17 May 2021 10:04

Hi Rahul,


Could you please try the steps described in this documentation article? The article steps are tested with Cisco VPN, but you could try using the same flow with the built-in VPN client. Notice that the execution order of the steps is crucial for the initial setup and for reusing the VPN client alongside Fiddler Everywhere.


Nick Iliev
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