Make sure to verify the signature if you’re using it in production. Also note that 1.2.10.0 is the file version as shown in DLL properties – the release is just called 1.2.10.

Here’s a clear, helpful forum-style post you can use or adapt: Where to download log4net version 1.2.10.0?

Does anyone know a reliable source for this exact old version (1.2.10.0)?