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With the introduction of the new Fiddler Everywhere client, we are also moving the forums and feedback portal to a new location. Please follow this link to the new forum experience, use your existing Fiddler Everywhere credentials to login, and post any questions you may have. 

The existing Fiddler Everywhere forum will be locked and users won't be able to create new threads or update existing ones. The forum will remain available in read-only state.

Top achievements
Rank 1
 asked on 29 Jul 2020
1 answer

Why would a https page work successfully when running a fiddler capture but then when i close fiddler, the page no longer works?
I have the decrypt https traffic options selected 

How would i get that to stop so i can capture why page does not work under normal circumstances? 

Nick Iliev
Telerik team
 answered on 20 May 2022
1 answer

Hello all,

I have seen various threads about this topic but although I followed all the recommendations, nothing had a successful result. I have installed fiddler on my new Win10 laptop. Hotspot is created through NoWifi windows app since the driver does not directly support hotspot. Mobile is connecting normally to the hotspot and has access to internet without a problem (sharing my ethernet with the mobile hotspot). When I modify the wifi connection on the mobile to give the ip and port for the fiddler proxy, the mobile has no access to the internet any more.

Fiddler has:

  • Enabled Capture HTTPS CONNECTs
  • Enabled Decrypt HTTPs traffic
  • Enabled Allow remote computers to connect

And has been restarted after the settings have configured.

When I connect to the wifi with the mobile, I try to reach the ipv4.fiddler:8888/ page but I get Site can't be reached...

I have also tried to change the certificate generator to BouncyCastle but this did not work either.

Any ideas would be greatly appreciated.

Thank you very much,


Top achievements
Rank 1
 answered on 17 May 2022
2 answers



Does Fiddler Everywhere support websockets?

If it does how can I enable it?

Thank you in advance.

Nick Iliev
Telerik team
 answered on 13 May 2022
1 answer


I wanna know whether Progress Telerik Fiddler Web Debugger and fiddler classic actually is a same software, only with different name or different version?




Nick Iliev
Telerik team
 answered on 12 May 2022
1 answer

Hi everyone,

After hours of using the Progress Telerik Fiddler Classic, i'm blocked. I'm trying to intercept a web socket secure (WSS) over TLS, that's why I'm using the HTTPS MITM Proxy.

I have registred all the SSL Root certificates and everything is working. But when I show the Web socket inspector, I couldn't translate the binary to human readable text. After some researchs, it seems that I need to decode the payload ?

Does FiddlerClassic permit to translate the binary of a web socket frame to the text human readable ?

Here a screenshot:


Big thanks in advance for all your help. Have a nice end of day,


Nick Iliev
Telerik team
 answered on 10 May 2022
0 answers

I like to grab the ClientBeginRequest and convert that to UNIX epoch time in the Fiddler scripts, however, I cant seem to get the known methods to work like Math.floor. 

var iat = oSession.Timers.ClientBeginRequest; -> this does not give me unix time in sec

The idea is to generate json data with iat, exp and convert it to base64 and add it to the header

        if (oSession.HostnameIs("") && oSession.uriContains("/value/"))
            // Take ClientBeginRequest and convert it to unix
            //    var iat = oSession.Timers.ClientBeginRequest;
            //    var iat2 = Math.floor(iat / 1000);
            // Take the // Take ClientBeginRequest and convert it to unix + 30 mins
            //    var minutesToAdd=30;
            //    var exp = new Date(iat + minutesToAdd*60000);

            // convert json data to base64
            //    var obj = {iat: 'iat', exp: 'exp'};
            //    objJsonStr = JSON.stringify(obj);
    //    objJsonB64 = Buffer.from(objJsonStr).toString("base64");

            //Add the value to header
            oSession.oRequest["new-header-name"] = "headerValue in base64";



I have iat and exp working, just need some help with converting the value to base64. 

        import Microsoft.JScript;

        var iat = Math.round((new Date()).getTime() / 1000);
        oSession.oRequest["iat"] = iat
        var exp = (iat + 1800);
        oSession.oRequest["exp"] = exp
        var data = {iat: 'iat', exp: 'exp'};


Top achievements
Rank 1
 updated question on 09 May 2022
1 answer
i don't know why my computer shut down immediately when running Fiddler Classic, i opened the Fiddler and it opened but few seconds later my computer just Shutdown, pls anyone know what is this and how to fix it thank you
Nick Iliev
Telerik team
 answered on 09 May 2022
0 answers


I work on scraping data from the android app. i could see HTTP and HTTPS traffic but in special data that I want extracting didn't show in fiddler sessions. I attach fiddler certification on the android device and even try certificate pinning bypass approach with the Exposed framework, but still, I couldn't see traffics, this data is about the history of users and when I load this data and scroll some pages, nothing shows in fiddler, like I didn't anything.

Now my questions are about this problem.

First which network traffic cant see with fiddler and how can understand the type of my traffic to assay that?

Second how I could monitor this traffics? have fiddler any extensions to cover this? or this work could do anyway like other apps or other approach or use another framework like Frida?

got stuck with issue for a long time. appreciate your help, please.

Regards - ah.Mohammadi

Top achievements
Rank 1
 asked on 24 Apr 2022
2 answers

- I have Fiddler Anywhere Version : 3.1.1Built : Friday, April 1, 2022

- I'm getting the following error when trying to login to a site that uses Google Authentication



I have SSL enabled as well as HTTP 2