Plugin Registration Error

During registration of our plugins/custom code activities from plugin registration tool, we might faced following error

“Plug-in assembly does not contain the required types or assembly content cannot be updated.”

There can be multiple reasons of this error

Reason 1: You had some class file (inheriting from IPlugin) in your plugins project which you have deleted (may be you do not need it now). But, that is still there in registered plugins in CRM.

Solution 1: Unregister that plugin also from CRM by using plugin registration tool or Delete that directly using some solution from CRM.

Solution 2: There is a tool in XRM Toolbox named “Delta Plugins: Local Assembly vs CRM Assembly” which can help you identify the difference between your local assembly and CRM assembly.

Note: Following image is copied from post of Ravi from this thread on dynamics community.

Reason 2: You have renamed a plugin class in your plugin project but that exists in CRM with old name.

Solution: Unregister the plugin with old name from CRM or rename the class inherited from IPlugin to the same name as it exists in CRM.

Reason 3: You have used CRM DLLs or any other external system DLLs with higher or lower supported version than your current CRM version. For example, you added CRM DLLs from Nuget package manager, which will add DLLs of CRM Verion 9 of Dynamics 365 online. But, you are using Dynamics 365 OnPremise version 8.2.

Solution: Remove the DLLs references which are not compatible with your CRM version. Add the correct DLL references, then build and register the plugin again.

References:

https://community.dynamics.com/crm/f/117/t/243648