Could not load file or assembly log4net

Asked 27/10, 2014 at 9:28 Answered 24/3, 2022 at 7:55

I have added log4net to my project and it is working just fine on my machine, but when I sent the release version of my application to my colleague, he receives this FileNotFoundException:

Could not load file or assembly 'log4net, Version=1.2.13.0, Culture=neutral, PublicKeyToken=669e0ddf0bb1aa2a'

But the strange thing is that in my app.config I'm not even using the above version of log4net:

<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
<sectionGroup name="applicationSettings" type="System.Configuration.ApplicationSettingsGroup, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
<section name="BizWizard.Properties.Settings" type="System.Configuration.ClientSettingsSection, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false"/>
</sectionGroup>

Sandi answered 27/10, 2014 at 9:28 Comment(8)

Look at #8744492 May be this is what is needed in your case. – Veronique 27/10, 2014 at 9:33

@Veronique I am trying to do the fixes. But why is it working fine on my machine? – Sandi 27/10, 2014 at 9:40

I know this sounds stupid, but did you send the log4net DLL's with your application to your colleague? – Dimorphism 27/10, 2014 at 9:40

@BerndLinde yes both log4net.dll and log4net.xml are included in the folder. – Sandi 27/10, 2014 at 9:41

Are both systems 64bit? (Reference here) – Dimorphism 27/10, 2014 at 9:43

Do your colleague use "global assembly cache"? Are some of your dll's being loaded from somewhere else on his computer? – Porush 27/10, 2014 at 10:19

@JanPetterJetmundsen log4net is the only dll we are using in this program. – Sandi 27/10, 2014 at 10:20

Similar question here - Could not load file or assembly 'log4net, Version=1.2.10.0, Culture=neutral, PublicKeyToken=1b44e1d426115821' – Gaudette 22/7, 2021 at 6:11

Do you use other third party libraries? Maybe one of them requires this particular version of log4net. If this is the case, this can be resolved using assembly binding in your applications app.config file.

<runtime>
  <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
    <dependentAssembly>
      <assemblyIdentity name="log4net" publicKeyToken="669e0ddf0bb1aa2a" />
      <codeBase version="1.2.13.0" href="log4netv1.2.13.0\log4net.dll" />
    </dependentAssembly>
  </assemblyBinding>
</runtime>

and the put this the 1.2.13.0 version of log4net in a sub-folder called log4netv1.2.13.0

You may also try to redirecting all references to log4net to a specific (your) version using bindingRedirect. http://msdn.microsoft.com/en-us/library/7wd6ex19(v=vs.110).aspx

Porush answered 27/10, 2014 at 10:13 Comment(2)

I just downgraded to log4net 1.2.0 and it started working. Since I am not looking for problems in the future I think I'm gonna stick to this for now. – Sandi 27/10, 2014 at 11:36

put some folder, redirect... what are you talking about? All use nuget packages for years! they you can't simply put library in a folder you want and hack the problem! – Counterfoil 7/4, 2017 at 13:58

Ran into the same problem. LinqToExcel library was using different version of log4net.

To solve it:

Delete the old log4net version in References.
Go to Tools, Nuget Packet Manager, Package Manager Console.
Run:

Install-Package log4net -Version 2.0.3

More details here:

https://www.nuget.org/packages/log4net/2.0.3

Disuse answered 25/1, 2017 at 16:51 Comment(1)

The problem with this is, when something else has a dependency on the new version :( – Tetracycline 22/11, 2019 at 12:51

You can check in the Nuget-Package-Manager (Tools-->Nuget-Package-Manager) if you have installed the log4net-Package in other Projects of this solution as well. If so, you can upgrade them to the same version. That worked for me.

Stringhalt answered 24/3, 2022 at 7:55 Comment(0)

Recommended topics

Hot tags