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Why am i can't create certificate on lastest version(v4.6.20172.34691)?

My Environment:

  1. 64-bit AMD64
  2. .NET 4.5.2 WinNT 6.1.7601 SP1

I've tried two validation engines(MakeCert,CertEnroll).


The following error occurred when I was using the MakeCert engine:

Uncaught Exception in Session #32
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

未能从程序集“Fiddler, Version=4.6.20172.34691, Culture=neutral, PublicKeyToken=null”中加载类型“Fiddler.ICertificateProvider4”。

Type: System.TypeLoadException
Source: mscorlib
在 System.Reflection.RuntimeAssembly.GetExportedTypes(RuntimeAssembly assembly, ObjectHandleOnStack retTypes)

在 System.Reflection.RuntimeAssembly.GetExportedTypes()

在 Fiddler.CertMaker.Œ() 位置 C:\JenkinsHome\jobs\FiddlerReleaseBuild\workspace\Fiddler2\Common\Core\CertMaker.cs:行号 111

在 Fiddler.CertMaker.EnsureReady() 位置 C:\JenkinsHome\jobs\FiddlerReleaseBuild\workspace\Fiddler2\Common\Core\CertMaker.cs:行号 69

在 Fiddler.Session.(Session ) 位置 C:\JenkinsHome\jobs\FiddlerReleaseBuild\workspace\Fiddler2\Common\Core\Session.cs:行号 5583

在 Fiddler.Session.‘() 位置 C:\JenkinsHome\jobs\FiddlerReleaseBuild\workspace\Fiddler2\Common\Core\Session.cs:行号 3519

在 Fiddler.Session.(Object ) 位置 C:\JenkinsHome\jobs\FiddlerReleaseBuild\workspace\Fiddler2\Common\Core\Session.cs:行号 3347

Fiddler v4.6.20172.34691 (x64 AMD64) [.NET 4.0.30319.36373 on Microsoft Windows NT 6.1.7601 Service Pack 1]

  • Guest
  • Sep 16 2017
  • Under review
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  • Guest commented
    28 Sep, 2017 06:44pm

    Thanks,the problem has been solved.I changed a certificate engine and I'll do it later,but specific reasons I do not know.

  • Eric Lawrence commented
    19 Sep, 2017 08:31pm

    A new version of Fiddler was shipped this week, allegedly fixing this bug.

  • Eric Lawrence commented
    18 Sep, 2017 04:45pm

    This is probably a duplicate of Do you have problems with the CertEnroll engine? Is the error message the same?