Hi

I set a breakpoint after response and changed a value

then i hit the run to completion button an the changed value shows up in the browser but after a few seconds the old value displayed again

 

but there is no new traffic shown in fiddler

so why the change is not working?

I installed Fiddler (V4.6.0.2 - August 17 2015) on Windows 10 RTM (build 10240) x64 en-US.

Since then, Edge is no longer working (error "Hmm, we can't reach this page.") unless Fiddler is running.

Note that Firefox , Chrome and IE11 do not have this issue, they are OK when fiddler is NOT running.

I restarted the PC several times,the problem is still present.

I checked the ProxyServer key in HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings : the key is only there when fiddler is running.

Also I cannot sign in Windows Store or Groove Music unless Fiddler is running AND I've enabled the apps in  "App Container Loopback Exemption Utility" (WinConfig button).

Note #1: I have a warning  "Orphaned Exemption Record Found" when launching WinConfig, see attached screenshot.

Note #2: In HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings, I have this key : _FiddlerDirectWrite = "BuggyWinShutdown at 01:07:59 2015-09-17". I don't know if this is normal.

Note #3 : I searched every location in registry with value "8888" ( fiddler proxy port) when Fiddler was running then I closed Fiddler and looked at the registry locations again.

I found 8888 in those 2 keys below, so I deleted the keys, restarted the computer but the issue is still there.

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\iphlpsvc\Parameters\ProxyMgr\{E6EFF353-402B-45F2-8D72-E8B7FA394DB5}]
"StaticProxy"="http=127.0.0.1:8888;https=127.0.0.1:8888"
"ProxyBypass"="<-loopback>"
"LastUseTime"=hex(b):8a,ce,43,c6,ba,f0,d0,01

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\iphlpsvc\Parameters\ProxyMgr\{F9D45E1B-22AA-4CAA-BDA0-DA414B44C2A5}]
"StaticProxy"="http=127.0.0.1:8888;https=127.0.0.1:8888"
"ProxyBypass"="<-loopback>"
"LastUseTime"=hex(b):8a,ce,43,c6,ba,f0,d0,01

 

From HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\NetworkList\Profiles, I can see that:

{E6EFF353-402B-45F2-8D72-E8B7FA394DB5} is "fortissl" : Fortinet SSL VPN that I use to connect to my company network.

{F9D45E1B-22AA-4CAA-BDA0-DA414B44C2A5} is "Network" : Ethernet connection

After I ran fiddler, the key {F9D45E1B-22AA-4CAA-BDA0-DA414B44C2A5} was re-created.

The other key {E6EFF353-402B-45F2-8D72-E8B7FA394DB5} would probably have been re-created as well if  VPN connection was established when I ran fiddler again.

Fortinet SSL VPN​ is working fine, I installed it right after Windows 10.

I had no issue  with Edge or Windows Store until I installed Fiddler 4.

 

hello
screenshot is attached

 

best regards, jan

I got a new machine and I added the code below according to this post. https://www.telerik.com/forums/remove-all-as-a-single-click-button-on-the-toolbar
Now after clicking on the BYE button, it clears the entries but Fiddler stops capturing anything from any site anymore. It only work once once I restart Fiddler.
It used to work on my old machine. I can't figure out what is different here.



 static function RemoveAll(s: Object, e: EventArgs)
    {
        FiddlerApplication.UI.lvSessions.Clear();                   
    }
    
    static function OnBoot() {
        
        try {
            for (var c in FiddlerApplication.UI.Controls)
            {
                if (c.GetType().Name == "ToolStrip")
                {
                    var ts: ToolStrip = c;
                    var tsi: ToolStripButton = new ToolStripButton("BYE!");
                    tsi.add_Click(RemoveAll)
                    ts.Items.Insert(0, tsi);
                }
            }
        } catch(e) { FiddlerApplication.Log.LogString(e); } 
        
    }

Hello,

Is there any way to decrypt TLS 1.3 yet? Some app's have started using TLS 1.3 only, so proxying my phone through Fiddler leaves me with undecryptable tunnels only.

 

An example of such a capture is attached.

 

Best regards,

Jack

Is there a way to have Fiddler not update the FiddlerScript rules file (CustomRules.js) in case the file contains any errors?

I use Fiddler to block some traffic, but in case the rules file contains even a small error, then Fiddler will drop all the rules inside the file and allow all traffic to pass.

The best solution would be to first check the validity of the file, and only update it in case it contains no error at all.

I woulnd't mind automating this through a Perl script, but I still need a way to interogate Fiddler over the validity of the file.

In case there is no easy way to do this, my only option would be to write a Perl script that will initiate a web connection that is supposed to be blocked by Fiddler. In case it is not blocked, I can only assume the rules file I had just updated right before initiating the connection contains an error. In this case, the Perl script would kill Fiddler, replace the rules file with the previous version, and restart Fiddler. Everything should not take more than just a few seconds. This way, even if the file is not valid, Fiddler will continue to apply the rules (and block the traffic I need to filter out). My only problem with this solution is that it will take me some time to code it. I am looking for a more elegant, quicker way to do it.

Thank you,

Alex

Hi guys

We use ninitepro which runs in the background and updates applications like Chrome/Adobe etc on our computers. Since it doesn't have an active window I can't see what it is connecting to via Fiddler and I'm trying to figure out how to enable scanning of background processes so Fiddler will pick it up.

Thanks

Gerry

My aim is to log all requests coming to IIS10 server on the Windows Server 2016 from any customer.

A request is called with the port 80. Fiddler should redirect all requests to IIS on the port 8888. 

I made all steps described by Eric Lawrence:

If you want Fiddler to capture traffic coming *in* to your IIS server and going *out* from your IIS server, then you need to run Fiddler in both reverse proxy mode and normal proxy mode. First, get Fiddler capturing the traffic coming out from your IIS server (by editing machine.config & setting the proxy settings for WinHTTP to 127.0.0.1:8888, etc). Then, move your IIS instance to a different port (8080) and configure Fiddler to listen on port 80 as well (e.g. type !listen 80 in QuickExec to set up a second listening endpoint). In FiddlerScript, you then need to forward requests received on port 80 to your IIS instance (8080).

source https://www.telerik.com/forums/capture-all-iis-traffic-on-the-web-server

I see endless loop of requests sent from Fiddler to IIS. Only one request is sent from a client machine( tested also with Fiddler). Also after I disable "Capture Traffic" the outgoing requests to IIS are logged in Fiddler. 

Configuration

IIS domain binding set to the port 8888

Machine.config

<system.net>
    <defaultProxy>
        <proxy autoDetect="false" bypassonlocal="false" proxyaddress="http://127.0.0.1:8888" usesystemdefault="false" />
    </defaultProxy>
</system.net>

Custom rules in Fiddler:

if (oSession.host == "xxx.com:80") 
{
oSession.host = "xxx.com:8888";
}

Allow remote computers to connect set to true in Fiddler.

What can be wrong in the configuration?

 

 

 

 

 

Hi there!

 

How to configure fiddler in non-proxy mode?? So it listens to ALL http(s) connections from EVERY application that uses that protocol? Like wireshark...

Is that possible, i think not, right?

Thx for feedback.

 

Regards,

Jan

Hello. I am changing the post request body through a script:

 

If I do not change the request body, the server accepts it (301). If I use a script, the server throws an error (401). The data in replace.txt is completely identical to the data from the original request that the server accepts. What could be the problem?