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Daniel
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 updated question on 26 Dec 2024
7 answers
1.3K+ views

While playing around with windows 10 and looking for ways to ensure it will Shut the F*** up and break up with M$ I noticed that the various privacy violating services seam to respect the proxy configuration in the internet options.

So I installed fiddler on my test VM and enabled SSL decryption.

For some requests like windows update that seamed to work just fine,

but for the interesting telemetry once, it fails with error 408, for example requests to watson.telemetry.microsoft.com

The textView window says "The request body did not contain the specified number of bytes. Got 0, expected 1.359"

So I think its a bug with fiddler (or the lack of support for some protocol version) rather than M$ cooking up their own super secret SSL replacement.

 

So it would be great if the makers of fiddler could fiddle around a bit with this issue and solve it please :)

David
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Iron
 answered on 18 Dec 2024
1 answer
144 views

Hi,

We are unable to execute any with Power apps  in Desktop application when Fiddler Trace is active, it keeps loading forever and after closing Fiddler it works fine.  Could you please advise?

Thanks in advance.

Victor Pontes

Nick Iliev
Telerik team
 updated answer on 09 Dec 2024
1 answer
71 views

Hey,

 

since tonight (nothing changed on my Side I believe), randomly some Websites stopped to appear on Fiddler Everywhere MacOS in Capture Mode.

When I surf around / facebook / mmo-champion etc. (just example pages) they appear as Connect Tunnel opened but no content is seen.

So the Websites no longer get shown in the Traffic Window, just the Connect Tunnels.

I tried to uninstall Fiddler Everywhere, Resetting Configs by removing the Transprancy Proxy from MacOS but nothing seems to help, is there any instance I can check, why some websites randomly disappear and not coming back on MacOS? 

Do I need to "listen" on more Ports or so?

Nick Iliev
Telerik team
 answered on 02 Dec 2024
1 answer
120 views

I am using Windows 10 (it may work fine on Windows 11).

I was unable to capture the link below using Fiddler Classic and Fiddler Everywhere (trial version).

I think Fiddler Everywhere does not support TLS 1.3 successfully in Windows 10. If there is a way to force the connection to TLS 1.3 in Fiddler Everywhere, it may work, but I could not find such a setting.

I have confirmed that 3rd party network capturing tools successfully capture the link below, but why only Fiddler Classic and Everywhere fail? If Windows 10 does not fully support TLS 1.3, then 3rd party capturing tools should not work either, but since 3rd party programs work perfectly, I am wondering why this symptom only occurs in Fiddler.


1. Turn on Fiddler Classic or Everywhere and capture the link below, and it will be rejected.
2. Turn off Fiddler and access the link below, and it will work normally.

https://smartstore.naver.com/powermtb/products/6236194845

Nick Iliev
Telerik team
 answered on 27 Nov 2024
1 answer
85 views

Why does the POST request custom reply file not work?

GET asks him to be able to reply normally with a local file!

Nick Iliev
Telerik team
 answered on 25 Nov 2024
1 answer
111 views

fiddler-everywhere-5.21.0.AppImage runs successfully on a Fedora 37 workstation. On a Fedora 41 workstation it throws a System.TypeInitializationException and reports " Fiddler.WebUi is tampered" and fails to start the server.:

09:08:37.489 › Trying to start server at port [16197].
09:08:37.617 › Server error log during start: Unhandled exception. 
09:08:37.632 › Server error log during start: System.TypeInitializationException: The type initializer for '<Module>' threw an exception.
 ---> System.Exception: Fiddler.WebUi is tampered.
   at MaoFcf2Vq4taIANM6n.hIDAYxH6DWLHIthQgC.zSLipEDdx()
   at .cctor()
   --- End of inner exception stack trace ---

The checksum on the AppImage file is the same on both FC37 and FC41 workstations. It fails on a clean FC41 installation as well as on another system that was upgraded from FC38 to FC41. Full "script" log attached. Am I missing some preparation or is this a bug?

Nick Iliev
Telerik team
 answered on 25 Nov 2024
1 answer
60 views

Hello,

Pretty new to Fiddler, I'm using Fiddler Everywhere 5.21.0 .

What I'm trying to achieve is to replace the status code of a call to an identity server with 401, but just once.

I've created a following rule

Conditions:

When any of these conditions are met specific number of times: 1

URL Contains [Identity Server]/connect/token

 

Actions:

Update status code: 401

 

However, live traffic shows that when a /connect/token request is sent out, its status code is 200.

Only when I increase

When any of these conditions are met specific number of times: 2

A /connect/token request (a singular one, based on the Live Traffic view) will have its status code replaced to 401.

Why is that the case? Does the Live View actually filter out some traffic?

 

Thanks for bearing with my silly questions.

Zhivko
Telerik team
 answered on 21 Nov 2024
1 answer
97 views

How is possible select a target (e.g. an opened application) ?

I mean that in the classic fiddler is possible to drag the "target" icon over any app or browser, which you like to inspect

 

Thank you

Nick Iliev
Telerik team
 answered on 17 Nov 2024
1 answer
741 views

Hi, i get this error on any site any browser, 

when i looked at the certificate list, i see that the certificate is expired:

 

i just reinstalled the last version, but the problem persists

is there any way to fix that ?

Nick Iliev
Telerik team
 answered on 11 Nov 2024
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