---
title: Getting log4net Errors When Attempting to Browse Sitecore Pages
slug: '2183'
canonical_url: https://docs.coveo.com/en/2183/
collection: coveo-for-sitecore-v5
source_format: adoc
---
# Getting log4net Errors When Attempting to Browse Sitecore Pages


[.version.c4sc.c4sc-issue-resolved.5-0-761-5.August-10&-2020]
[Issue resolved](https://docs.coveo.com/en/3279#release-notes)


## Description

The `log4net.dll` file in the `<SITECORE_INSTANCE_ROOT>\website\bin` folder was changed and you're now seeing errors like the following when attempting to browse your Sitecore pages:

`Could not load file or assembly 'log4net, Version=1.2.11.0, culture=neutral, PublicKeyToken=669e0ddf0bb1aa2a or one of its dependencies.
The located assembly's manifest definition doesn't match the assembly reference…`

### Explanation

Coveo for Sitecore uses its own version of `log4net.dll`.
This custom version of `log4net.dll` is `1.2.11.0`.

The Coveo for Sitecore version of the `log4net.dll` needs to be in the `bin` folder of your website in order for it to work properly.

> **Note**
>
> Whenever you're installing a Coveo for Sitecore package, it will automatically overwrite any version of `log4net.dll` in `<SITECORE_INSTANCE_ROOT>\website\bin`.

### Resolution

To use a `log4net.dll` file other than the Coveo for Sitecore custom version, you must install that dll in a folder other than `bin`.
Therefore, create a separate folder for your version of `log4net.dll` and explicitly tell Sitecore where to get it.

. In the `<SITECORE_INSTANCE_ROOT>\website` directory, create a folder named `log4netCustom`.
The path to this folder will be `<SITECORE_INSTANCE_ROOT>\website\log4netCustom`.

. Move your `log4net.dll` (1.2.XX.0) file into the `log4netCustom` folder.

. Open the Sitecore `web.config` file.

. Locate the `assemblyBinding` element.

. Insert the following XML snippet inside the `assemblyBinding` element.

```xml
<dependentAssembly>
  <assemblyIdentity name="log4net" publicKeyToken="669e0ddf0bb1aa2a" />
  <codeBase version="1.2.XX.0" href="log4netCustom\log4net.dll" />
</dependentAssembly>
```