Hi everyone,

I have an .net framework 4.7.2 C# WPF app running which also has a little .net 3.5 app inside it.

This is running 1500 computers in australia and has been for 18 months.

Today we started getting reports of computers having 'crashes'

Debugging has provided this info:

section: created rest options System.Net.Http.HttpRequestException: An error occurred while sending the request. ---> System.Net.WebException: The request was aborted: Could not create SSL/TLS secure channel.

What we have now found out is that it is Windows 7 clients all being affected.

Importantly:

Postman and google chrome can access the api

JUST the .net seems ot be having issues.

After seeing this I have downlaoded fiddler (for first time) and we are seeing a handshake issue:

fiddler.network.https> HTTPS handshake to www.mydomain.com.au (for #710) failed. System.Security.Authentication.AuthenticationException A call to SSPI failed, see inner exception. < The message received was unexpected or badly formatted

Win32 (SChannel) Native Error Code: 0x80090326


But then when i booted fiddler im also seeing the same issue:

[Fiddler] The connection to 'api.getfiddler.com' failed.  <br />System.Security.SecurityException Failed to negotiate HTTPS connection with server.fiddler.network.https&gt; HTTPS handshake to api.getfiddler.com (for #1) failed. System.Security.Authentication.AuthenticationException A call to SSPI failed, see inner exception. &lt; The message received was unexpected or badly formatted

Win32 (SChannel) Native Error Code: 0x80090326                                       

 

 

So maybe the fiddler API is in fact having the same connection issue as I do, but maybe thats not really going to be noticed because its an update checker for their API but mine is my whole app??

 

Any ideas would be appreciated.

 

hi there

on windows 2022 server when i close fiddler or stop capture traffic

running apps can nor connect tls 1.2

i always get errors for service connecting until start capturing.

What should I do to make the system work properly when the program is closed?

 

Thaks for your help :)

I just need to sync the last decent, tolerable version of Evernote one more time: https://www.reddit.com/r/Evernote/comments/1cico6e/solutions_for_syncing_the_legacy_v6_client/

How can I do this?  I can't find a way to change the user-agent globally for running programs under WINE.  It's supposedly possible under FIDDLER but I'm new. :(  Help?  I searched the documentation and program, but I must not be good at this because I couldn't figure it out.

This happens when running Fiddler Everywhere for the first time, I've tried reinstalling it multiple times, running as Administrator and nothing.

 

I'm running on a Windows 11 pro, it's my personal computer there are no network blockers, I can ping the endpoints mentioned in this answer: https://www.telerik.com/forums/unable-to-accept-the-eula-please-try-again-later-if-the-problem-persists-please-contact-support

 

我一直在寻找Fiddler Everywhere 5.4.0版本中的自动回复功能，但一直没有找到。请问是取消了还是去哪里了？

I try many library, last library I try was global-tunnel-ng, but still have no result. Usually I use fiddler to trace various request, my Fiddler listen port 8888, therefore I try to use

I expected to see all request on Fiddler, but there are nothing any request on Fiddler panel. 'localhost' and '127.0.0.1' as ProxyURL also don't working. What I doing wrong?

I try many library, last library I try was global-tunnel-ng, but still have no result. Usually I use fiddler to trace various request, my Fiddler listen port 8888, therefore I try to use

 

  var globalTunnel = require('global-tunnel-ng');
  globalTunnel.initialize({
    host: 'ipv4.fiddler',
    port: 8888,
  });

  // my various request to Google, to AWS and more

  globalTunnel.end()
I expected to see all request on Fiddler, but there are nothing any request on Fiddler panel. 'localhost' and '127.0.0.1' as ProxyURL also 
don't working. What I doing wrong?
 

Hi

I am using Fiddler Classic v.5.0.20242.10753 for .NET 4.6.2 64-bit on Windows Server 2012R2 (don't ask!)

I am also using FiddlerScript in C# mode.  My use case is that I am trying to create a temporary fix for a legacy service that is responding with incorrectly derived values in an XML payload.  I can force all clients of this service to access it via Fiddler as a proxy, and I wanted to use FiddlerScript to modify the response to correct some of the data, as it can be derived from other parts of the response.

I did a very very rough PoC by catching the specific calls in OnBeforeResponse and making an arbitrary change.  What I have then tried to do is use the System.XML XmlDocument object, pass it the response body when instantiating, and working from there.

THE PROBLEM:  I have added "using System.XML;" to the script.  I have also added "C:\Windows\Microsoft.NET\Framework64\v4.0.30319\System.XML.dll" to the References field in Fiddler under Tools -> Options -> Scripting and restarted Fiddler Classic.  However, when saving the script, I get an error "The type or namespace name 'XML' does not exist in the namespace 'System' (are you missing an assembly reference?)"

I have tried just about everything I can think of to make that reference:
 - adding directly to the dll in the Windows dir
 - copying the dll(s) to the same DIR as the Fiddler.exe (as suggested in your docs)
 - adding the XML dlls to the GAC

Nothing I do seems to solve this problem.  I thought it might be a .NET version issue, but I have 4.6.2 installed.

How do I properly reference other .NET assemblies that I want to use in script? 

Thanks,
Steve.

After update updating Edge browser to version 124.0.2478.51，when access website I get  "Your connection is not private" 

I have configured Windows to trust Fiddler's root certificate.

I set fiddler " !listen 8889 *.acs.org " and set " fiddler.network.https.SetCNFromSNI true"  It works well  before update edge browser.

After update edge when i access pubs.acs.org it is ok.

but when i access pubs.rsc.org i get   "Your connection is not private" 

 I think this is because someing make fiddler  cannot automatically match certificates .

Please help me fix it ,thanks so much!

 

I thought maybe I was imagining this, but I can consistently reproduce it. Problem started with Fiddler Classic, and I then tried Fiddler Everywhere only to see the same behavior:

My dev/debugging environment consists of MS Visual Studio, Postman, and Fiddler running on Windows 10. I always have MS Outlook, MS Teams, and SSMS running as well. I run both Visual Studio, Postman, and Fiddler as Administrator, though I've tried running them in normal mode as part of debugging this problem. It makes no difference.

Any time I start Fiddler, within approximately 15 minutes, Teams is the first app to go down... it suddenly reports "no internet connection" and I can't send or receive messages.

Shortly thereafter, Outlook will start throwing up "invalid security certificate" dialogues. Email send/receive is no longer possible after this point... The Outlook Icon in my taskbar shows a yellow triangle with a black exclamation mark.

Next to go is the ability to make https connections through, for example, Chrome or Edge.  I see errors such as the attached.

Has anyone else experienced this behavior? I've tested extensively making sure just the apps I've mentioned earlier were running. I can run for 24, 48, or more hours without the problem occurring. But if I fire up Fiddler (either Classic or Everywhere), 100% of the time, the networking issues occur. Always.

Any thoughts on what might be going on here? My assumption is that Fiddler is trying to be a proxy for everything on my machine, and it just can't do it for <reasons>. If I remember correctly I can manually tell Fiddler NOT to proxy for certain apps, but this seems tedious. I'm especially worried to suddenly see https disabled for Chrome or Edge, as the Visual Studio applications I'm debugging are APIs that use https...