Hallo,
I'm stuck with this since weeks so I'm looking for each possible explanation for this scenario:

I open a site with Firefox and it works. I open the same site with Chrome and I do get a 404 response. BUT if I start fiddler and run a request concerning this site, it also works with Chrome - responding with 200 of course. This even lasts when I close fiddler but it stops working as soon as I clear my Chrome Browser settings.

I did check the proxy settings on both browsers. They're both set to 'use system proxy settings'. So I don't have any clue what might cause this behaviour and I'm wondering if I've overseen anything that fiddler has an impact on..
Any help is highly appreciated.
Thanks

I've noticed an issue when exporting data as HAR where the output is not binary identical to what was sent on the network. Specifically in my case one of the pages was UTF-8 encoded with BOM and that information was lost. I'd like to know whether there's a way of exporting all pages as base64 (like in the case of images) in order to preserve the page exactly as it was sent on the network.

Thank you.

I am receiving this error message upon launching Fiddler 4:

---------------------------
Loading custom MIME mappings failed
---------------------------
Fiddler has encountered an unexpected problem. If you believe this is a bug in Fiddler, please copy this message by hitting CTRL+C, and submit a bug report at http://www.telerik.com/forums/fiddler.

There is an error in XML document (0, 0).

Type: System.InvalidOperationException
Source: System.Xml
   at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle, XmlDeserializationEvents events)

   at System.Xml.Serialization.XmlSerializer.Deserialize(Stream stream)

   at Fiddler.XmlFileMimeMappings..ctor(String filePath) in C:\Jenkins\Fiddler_Windows\workspace\FiddlerCore\FiddlerCore.Shared\Common\Core\MimeMapping\XmlFileMimeMappings.cs:line 41

   at Fiddler.frmViewer.š(Object , EventArgs ) in C:\Jenkins\Fiddler_Windows\workspace\Fiddler2\Fiddler.Shared\Viewer.cs:line 9968

System.Xml.XmlException: Root element is missing.

   at System.Xml.XmlTextReaderImpl.Throw(Exception e)

   at System.Xml.XmlTextReaderImpl.ParseDocumentContent()

   at System.Xml.XmlReader.MoveToContent()

   at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReaderList1.Read3_ArrayOfMimeMap()
Fiddler v5.0.20202.18177 (x64 AMD64) [.NET 4.0.30319.42000 on Microsoft Windows NT 10.0.18363.0] 
---------------------------
OK   
---------------------------

Windows 10

---------------------------
Awww, Fiddlesticks!
---------------------------
Fiddler has encountered an unexpected problem. If you believe this is a bug in Fiddler, please copy this message by hitting CTRL+C, and submit a bug report at http://www.telerik.com/forums/fiddler.

The composition produced a single composition error. The root cause is provided below. Review the CompositionException.Errors property for more detailed information.



1) The specified quota list is internally inconsistent with its descriptor



Resulting in: An exception occurred while trying to create an instance of type 'Telerik.NetworkConnections.NetworkConnectionsManager'.



Resulting in: Cannot activate part 'Telerik.NetworkConnections.NetworkConnectionsManager'.

Element: Telerik.NetworkConnections.NetworkConnectionsManager -->  Telerik.NetworkConnections.NetworkConnectionsManager -->  AssemblyCatalog (Assembly="Telerik.NetworkConnections, Version=0.1.2.0, Culture=neutral, PublicKeyToken=67cb91587178ac5a")



Resulting in: Cannot get export 'Telerik.NetworkConnections.NetworkConnectionsManager (ContractName="Telerik.NetworkConnections.NetworkConnectionsManager")' from part 'Telerik.NetworkConnections.NetworkConnectionsManager'.

Element: Telerik.NetworkConnections.NetworkConnectionsManager (ContractName="Telerik.NetworkConnections.NetworkConnectionsManager") -->  Telerik.NetworkConnections.NetworkConnectionsManager -->  AssemblyCatalog (Assembly="Telerik.NetworkConnections, Version=0.1.2.0, Culture=neutral, PublicKeyToken=67cb91587178ac5a")



Type: System.ComponentModel.Composition.CompositionException
Source: System.ComponentModel.Composition
   at System.ComponentModel.Composition.Hosting.CompositionServices.GetExportedValueFromComposedPart(ImportEngine engine, ComposablePart part, ExportDefinition definition)

   at System.ComponentModel.Composition.Hosting.CatalogExportProvider.GetExportedValue(CatalogPart part, ExportDefinition export, Boolean isSharedPart)

   at System.ComponentModel.Composition.Primitives.Export.get_Value()

   at System.ComponentModel.Composition.ExportServices.GetCastedExportedValue[T](Export export)

   at Fiddler.Proxy.() in C:\Jenkins\Fiddler_Windows\workspace\FiddlerCore\FiddlerCore.Shared\Common\Core\Proxy.cs:line 283

   at Fiddler.Proxy..ctor(Boolean isPrimary, ProxySettings upstreamProxySettings) in C:\Jenkins\Fiddler_Windows\workspace\FiddlerCore\FiddlerCore.Shared\Common\Core\Proxy.cs:line 210

   at Fiddler.frmViewer.‹•(String[] ˆ•) in C:\Jenkins\Fiddler_Windows\workspace\Fiddler2\Fiddler.Shared\Viewer.cs:line 3339

   at Fiddler.frmViewer.‡•(String[] ˆ•) in C:\Jenkins\Fiddler_Windows\workspace\Fiddler2\Fiddler.Shared\Viewer.cs:line 3164


Fiddler v5.0.20202.18177 (x64 AMD64) [.NET 4.0.30319.42000 on Microsoft Windows NT 10.0.19041.0] 
---------------------------
OK   
---------------------------

Hello,

Is there a way to script Fiddler via code? I want to be able to set up fiddler with AutoResponder enabled automatically and an imported .saz file and then run some test automation where Fiddler automatically responds. All of this needs to be done programmatically as part of a test suite. Does something like this already exist?

Hello, I am writing to you because I have a problem with fiddler, the problem is that it does not capture the traffic of the pages I have tried installing the new version and everything, but on my old pc if it captures the traffic of the pages, I would like to know how I could solve this problem, which only happens to me on this PC.

thanks for watching, and sorry for my bad english.

Am i able to collect data from my phone via fiddler without using WIFI? I prefer the high speed internet a cable provides me with, but i am unsure where to put in my proxy settings in the phone if i do decide to use a ethernet cable to connect to the internet 

Hi Team,

I have installed fiddler on my company laptop

From my laptop I am able to see the Fiddler Echo Service Page, even I can see all the traffic running on my laptop.

But when I try to connect my android mobile( connected to the same wifi which laptop connected and also able to ping my mobile device) and do proxy changes

I don't see the fiddler echo service page in my mobile

I don't see any mobile traffic on Fiddler

Mobile is not able to access internet

Can anyone help me with this issue?

There is some command line tools or handlers to save the traffic and filtering while run?

I need to run automation tests and save the traffic captured of the tests failed. My idea was to save every time a file is created in a specific folder (meaning test failed) and ignore those ones passed, in a way of fiddler is open and close every time a test is started and finish respectively.

Best regards,

Salvado

 

 

Hi,

  I downloaded Fiddler Classic v5.0.20202.18177.  When I attempt to install it, it stops working at the Setup Helper step.  A message appears that reads "Fiddler.SetupHelper has stopped working".  If I click 'Close Program', a warning dialog appears that reads "error code: 255.  Please add Progress Telerik Fiddler's installation directory to your PATH environment variable if you want to be able to start Progress Telerik Fiddler from the Windows' Run dialog."

  After closing that dialog, Fiddler appears to finish installing.  However, although it is listed in the Control Panel's installed programs, it does not start up after I click the application executable.

  I have tried adding the installation directory to my PATH environment variable and restarting my PC, but it does the same thing.  I have tried uninstalling it, and reinstalling, but to no avail.  I have tried turning off my firewall, uninstalling it, and installing it, all while the installation directory was added to my PATH environment variable.  I have tried installing it to my Desktop instead of the default directory.  I have tried fresh downloads of Fiddler Classic.  I have tried installing it while my anti-virus is disabled.  At this point, I'm not sure what else to try; any help would greatly be appreciated.  I'd really like to give this program a go, because I've heard good things about it.  I'm including the installation details below, as well as several screenshots.

  Thanks in advance for your help!

 

 

Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler
No older version of Progress Telerik Fiddler was found.
.NETv4 Framework Key found.
Compatible .NET Framework/Service Pack found.
Installing Progress Telerik Fiddler
Extract: Fiddler.exe
Extract: Fiddler.exe.config
Extract: Fiddler.pdb
Extract: SetupHelper
Extract: TrustCert.exe
Extract: TrustCert.pdb
Installing Dependencies...
Extract: Be.Windows.Forms.HexBox.dll
Extract: Analytics.dll
Extract: Analytics.pdb
Extract: GA.Analytics.Monitor.dll
Extract: GA.Analytics.Monitor.pdb
Extract: Newtonsoft.Json.dll
Extract: Xceed.FileSystem.v5.4.dll
Extract: Xceed.Zip.v5.4.dll
Extract: Xceed.Compression.v5.4.dll
Extract: Xceed.Compression.Formats.v5.4.dll
Extract: App.ico
Extract: Countdown.wav
Extract: LoadScript.wav
Extract: LoadScriptError.wav
Extract: Screenshot.wav
Extract: credits.txt
Extract: saz.ico
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler\ResponseTemplates
Extract: 200_FiddlerGif.dat
Extract: 200_SimpleHTML.dat
Extract: 200_TransPixel.dat
Extract: 204_NoContent.dat
Extract: 302_Redirect.dat
Extract: 303_RedirectWithGet.dat
Extract: 304_NotModified.dat
Extract: 307_RedirectWithMethod.dat
Extract: 401_AuthBasic.dat
Extract: 401_AuthDigest.dat
Extract: 403_AuthDeny.dat
Extract: 404_Plain.dat
Extract: 407_ProxyAuthBasic.dat
Extract: 502_Unreachable.dat
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler\Scripts
Extract: SampleRules.cs
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler\Tools
Extract: Brotli.exe
Extract: JXR2PNG.exe
Extract: JXR2PNG.exe.config
Extract: Zopfli.exe
Extract: dwebp.exe
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler
Extract: license.txt
Extract: makecert.exe
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler\Scripts
Extract: SampleRules.js
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler
Extract: ExecAction.exe
Extract: ForceCPU.exe
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler
Installing NetworkConnections...
Extract: Telerik.NetworkConnections.dll
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler\Plugins\NetworkConnections
Extract: Telerik.NetworkConnections.Windows.dll
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler\Inspectors
Installing Progress Telerik Fiddler inspectors
Extract: Standard.dll
Extract: SyntaxView.dll
Extract: QWhale.Common.dll
Extract: QWhale.Editor.dll
Extract: QWhale.Syntax.dll
Extract: QWhale.Syntax.Schemes.dll
Installing tools...
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler\Tools
Extract: PngDistill.exe
Extract: PngDistill.pdb
Installing FiddlerExtensions...
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler\Scripts
Extract: SimpleFilter.dll
Extract: SimpleFilter.pdb
Extract: Timeline.dll
Extract: Timeline.pdb
Extract: RulesTab2.dll
Extract: QWhale.Common.dll
Extract: QWhale.Editor.dll
Extract: QWhale.Syntax.dll
Extract: QWhale.Syntax.Parsers.dll
Installing Fiddler Orchestra addon...
Extract: FiddlerOrchestra.Addon.dll
Extract: FiddlerOrchestra.Addon.pdb
Extract: FiddlerOrchestra.Connection.dll
Extract: FiddlerOrchestra.Protocol.dll
Extract: FiddlerOrchestra.Utilities.dll
Extract: netstandard.dll
Installing Fiddler Script Editor...
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler\ScriptEditor
Extract: FSE2.exe
Extract: FSE2.exe.config
Extract: QWhale.Common.dll
Extract: QWhale.Editor.dll
Extract: QWhale.Syntax.dll
Extract: QWhale.Syntax.Parsers.dll
Extract: Analytics.dll
Extract: Analytics.pdb
Extract: GA.Analytics.Monitor.dll
Extract: GA.Analytics.Monitor.pdb
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler\ImportExport
Extract: BasicFormats.dll
Extract: BasicFormats.pdb
Extract: VSWebTestExport.dll
Extract: VSWebTestExport.pdb
Write x64 HKLM Keys
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler
Create shortcut: C:\Users\Sam\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Fiddler 4.lnk
Create shortcut: C:\Users\Sam\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Fiddler ScriptEditor.lnk
Registering Windows Firewall Exception for inbound traffic...
ExecShell: C:\Windows\system32\netsh.exe
ExecShell: C:\Windows\system32\netsh.exe
Invoking DotNet4 64bit NGEN
ExecShell: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\ngen.exe
ExecShell: C:\Windows\Microsoft.NET\Framework64\v4.0.30319\ngen.exe
Execute: "C:\Users\Sam\AppData\Local\Programs\Fiddler\SetupHelper" /a "C:\Users\Sam\AppData\Local\Programs\Fiddler"
Output folder: C:\Users\Sam\AppData\Local\Programs\Fiddler
Extract: uninst.exe
Refreshing icons...
Completed