Last Updated: 21 Aug 2020 15:00 by ADMIN
Created on: 14 Aug 2020 17:19
Type: Bug Report
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I was using Fiddler, working with AutoResponder, and hit an object reference not set error. I didn't notice anything obvious not working after dismissing the error.

I don't have exact repro steps, but thought I would pass along the stack trace.


Uncaught Exception in Session #118
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

Object reference not set to an instance of an object.

Type: System.NullReferenceException
Source: Fiddler
   at Fiddler.AutoResponder.(Session , ResponderRule ) in C:\Jenkins\Fiddler_Windows\workspace\FiddlerCore\FiddlerCore.Shared\Common\AutoResponder.cs:line 1787

   at Fiddler.AutoResponder.(Session ) in C:\Jenkins\Fiddler_Windows\workspace\FiddlerCore\FiddlerCore.Shared\Common\AutoResponder.cs:line 2026

   at Fiddler.Session.() in C:\Jenkins\Fiddler_Windows\workspace\FiddlerCore\FiddlerCore.Shared\Common\Core\Session.cs:line 5414

   at Fiddler.Session.‘() in C:\Jenkins\Fiddler_Windows\workspace\FiddlerCore\FiddlerCore.Shared\Common\Core\Session.cs:line 3628

   at Fiddler.Session.(Object ) in C:\Jenkins\Fiddler_Windows\workspace\FiddlerCore\FiddlerCore.Shared\Common\Core\Session.cs:line 3522

Fiddler v5.0.20202.18177 (x64 AMD64) [.NET 4.0.30319.42000 on Microsoft Windows NT 6.1.7601 Service Pack 1] 
1 comment
Posted on: 21 Aug 2020 15:00

Hello Casidy,

Thank for passing along. This helps us to make Fiddler a better product. I have added the bug to our backlog. Please, don't hesitate to contact us again if you manage to reproduce it.

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