In this tutorial, you will learn how to fix the Activation error occurred while trying to get an instance of type EPiDashboardController exception. I have encountered this error a few times now. The error usually occurs when Iam trying to get an existing Episerver website up and running. The exact error is shown below:

When this error occurs, it prevents the editor from loading. All you see whenever you try and log into the editor is a blank screen. This error can be a bit misleading and a bit annoying, as a) the issue is never a structure map issue and b) there isn't an easy way to find out what's gone wrong.

The first time I encountered this error was because the Episerver CMO plugin wasn't installed correctly. I was either missing an assembly or one of the web.config settings hadn't been applied correctly. The last time I had this error was pretty random. I needed to register my websites assembly in the modules.config, like this:

After adding the section to the config file, the editor started working as expected. If you've got a similar issue, then based on my experience the issue is probably related to a plug-in or an add-on issue. Check which addons your site uses and try re-installing them. An EPiDashboardController error usually means that something probably isn't registered correctly and Episerver requires some configuration information to be present in the web.config Episerver either can't talk to something, the config is wrong, or you have the wrong version of some files. While trying to fix my error, I noticed that someone has also solved this issue by applying the IUSER permission to the webroot.

To fix this issue, I first recommend registering the assembly the exception is moaning about in module.config. If that doesn't work, try going through and removing items contained within module.config. By removing things one line at a time you should be able to find what's breaking your site!

Working With Azure?

If you are working with an Azure web app and you encounter this issue, as mentioned in the comments below, by Matt. Try adding this line within your structure map config:

I am hoping the advice in this post lets you fix your issue! Let me know if it does in the comments below. Happy Coding 🤘