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Could not load file or assembly 'log4net, Version=


Upgrading EPiServer to the latest version, I get the error: 'Could not load file or assembly 'log4net, Version=, Culture=neutral, PublicKeyToken=1b44e1d426115821' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)'.

After some research I found out that EPiServer.Common.Framework.Impl.dll (version 7.5.446.0) has a different version reference on log4net.dll as EPiServer.Logging.Log4Net.dll (Version

EPiServer.Logging.Log4Net has a reference on log4net with Version and PublicKeyToken 669e0ddf0bb1aa2a.
EPiServer.Common.Framework.Impl has a reference on log4net with Version and PublicKeyToken 1b44e1d426115821.

Unfortunately I can't drive the assembly through web.config, because the PublicKeyToken has been changed.

This will not work:


You will not see the error if you have in your assembly cache (GAC, C:\Windows\assembly\) log4net Version

I have to wait of a new release from EPiServer.CommonFramework to fix this problem or is there any other way?

Thank you

Jan 12, 2016 15:01

Or you can downgrade EPiServer Logging

Install-Package EPiServer.Logging.Log4Net -Version 1.1.0

Jan 12, 2016 16:00
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