I have a user that reported issues trying to use "Fiddler Everywhere" after upgrading their OS:

"I updated from windows 10 to windows 11...Fiddler Everywhere was working last week when I was using on Windows 10. After upgrading, I tried to use it again today and cannot establish a remote connection to monitor traffic from a mobile device. I noticed when I first opened Fiddler I received a windows firewall notification. The option to "allow" was greyed out and I could only close the prompt. I am assuming the problem with connecting is related to the firewall but these seem to be managed by the organization. Please help allow traffic through Fiddler to assist in my debugging workflows."

I don't use Fiddler, and my team doesn't have internal documentation on troubleshooting Fiddler.  I enclosed some screen captures of what the user has sent us.  He is an Administrator on his Windows laptop, but I noticed some duplicate entries in his Windows Firewall that are grayed out, likely to Group Policy.

Any assistance would be greatly appreciated.

Hi,
I'm unable to access DuckDuckGo with Fiddler Everywhere. I can connect to DuckDuckGo without Fiddler. I think it's because DuckDuckGo detects Fiddler. Other possibilities are that the Fiddler certificate also supports unsafe TLS 1.0 and TLS 1.1, and their server ignores the request, but I'm not sure. Can you connect to DuckDuckGo, or is this issue exclusive to me? Thanks

This is what I received in the response. 

Delete my account

I need to capture URLs for Oracle SmartView logins. I saw some video for fiddler classic to setup. but can you help me to do the same set up ln enterprise.

https://youtu.be/syUoIw8N2WQ

pls provide the steps for enterprise:

 

When I try to analyse the requests on Yahoo Finance, I see different results when requesting from a browser with Fiddler turned on compared to the same request when Fiddler is turned off. I also tried different capture methods (System Proxy, Network Capture and Browser), but the same occurs. If I use this url:

 

https://query1.finance.yahoo.com/v8/finance/chart/IVV?events=capitalGain%7Cdiv%7Csplit&formatted=true&includeAdjustedClose=true&interval=1d&period1=0&period2=1747180800&symbol=IVV&userYfid=true&lang=en-US&region=US

 

Opening this url in a Chrome tab with Fiddler turned off, everything works fine (HTTP 200 response). Wih Fiddler turned on, however, the site responds with a HTTP 429 code (Too Many Requests).

 

Why this is happening?

Following guide online to swap out the old max speed with the new max speed but i'm using a mac whereas most people used fiddler classic on windows and i'm not sure whether I put the values in the correct places within the rule.  Anyone spot my noob mistake ?  Seems like many people had success so I know it's possible and my phone with the app making the API calls is connected properly to Fiddler that's not the problem. Please any help is so appreciated ! Thanks so much

websocket message garbled

Hello, for some tests, I'd like to use Fiddler to route through the corporate proxy network and, in a specific case, process requests/responses directly with mitmproxy scripts (because Fiddler Everywhere doesn't yet offer the same functionality as FC).

So I connect Fiddler to mitmproxy by setting the gateway proxy to mitmproxy listening at localhost:9090.

But it seems that Fiddler doesn't respect this setting. It always routes through the internet normally.
Even if I intentionally configure the wrong proxy port, the connection persists.

What should I do? Maybe I got wrong something??

 

I'm using Fiddler in Linux and already added certificates of Fiddler and mitmproxy to the system (actually i'm using the same one).

I keep getting this warning and as soon I click, I get it back. I think one of the security apps is monitoring and locking down the proxy server setting in Windows. I am running Fiddler as an admin and manually setting the proxy server but my setting is instantly removed.
It seems I can't use network sniffers that depend on certain proxy server settings.

Does Fiddler Anywhere suffer from the same issue?

I am using Fiddler Classic strictly for its FiddlerScript capabilities, and I have just learned that the Progress team no longer have any plans to add this awesome functionality to Fiddler Everywhere. This is very sad news for me, as I feel that probably Fiddler's most appreciated feature is dropped all together. I have just installed the Everywhere version, checked out its Rules tab, but I am most positive that all those hard-coded rules will not even come close to the functionality and the simplicity provided by a scripting language. The Rules tab in Everywhere may be a more easier and intuitive option for most users, but this comes at the price of loosing the flexibility and the powerful tools that only a script can provide. The web is becoming more and more complex with each day, and in order for Fiddler to stay on top of it, I believe it should give its users access to the most powerful tools available. Employing scripting capabilities is certainly one of it, if not the best one! Why restrict that?!

I would like to take this opportunity to kindly ask the design team to re-evaluate this decision of dropping this future. It sets Fiddler apart from all the other software out there, and dropping it all together would be a major downgrade for Fiddler, in my opinion. Having a Rules tab for those in need of a quick set-up, and preserving the current scripting capabilities for those looking for powerful functionality seems like the best way to go for me. With these two foundations, I have no doubt Fiddler will continue to stay relevant and grow in the years ahead.

Anyhow, in case no re-evaluation will be made and approved, I would like to know if you have any plans of dropping support/updates for Fiddler Classic in the future. This would be a second blow to all the 10 year+ Fiddler users.

I hope both versions will be offered to us for many years to come, no matter how much the web will be changing. So, please confirm if we can at least rely on Fiddler Classic, as some believe it is only a matter of time until it will be deprecated (including me). For the time being, hopefully the plans to add support for HTTP/2 and TLS 1.3 will indeed materialize (for Fiddler Classic).

If others feel like me on this whole issue, please do comment. Thank you!

Alex